Leech

* Alex Power - they became friends when Power Pack were captured (X-Men #195), and PP save Caliban from the Mutant Massacre (#27), later they are members of Future Foundation
* Amanda Sefton - both were in the Alley in X-Men #179, but maybe did not exactly meet then, but did meet at the wedding of Jean and Scott (#2.30)
* Angel - Leech becomes trainee in X-Factor after being saved from the Mutant Massacre (X-Factor #11)
* Annihilus - *Enemy:* they are antagonists in the FF Family Freakout storyline
* Apocalypse - *Enemy*: the X-Factor children are part of the city Christmas recovery after Apocalypse wrecked it (XF #27)
* Artie Maddicks - best friends since they first meet in the Alley (X-Factor #9), they both become adopted by first X-Factor, then X-Terminators, Generation X, and finally Future Foundation. Nickname: "Bigeyes" (X-Factor#10)
* Avalanche - they see each other after a battle between X-Factor and Alliance of Evil (X-Factor #33)
* Banshee - they meet at the wedding of Jean and Scott (X-Men #2.30), later Leech is adopted by Generation X
* Beast - first sees Beast when hiding in the Alley (X-Factor #10), is adopted by X-Factor after being saved from the Mutant Massacre (Power Pack #27)
* Bishop - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Black Knight - X-Factor battle a set of alien fake Avengers (XF #32)
* Blob - they see each other after a battle between X-Factor and Alliance of Evil (X-Factor #33)
* Boom-Boom - they were trainees in X-Factor together (from #12), and part of X-Terminators
* Cable - the X-Factor trainees learn about baby Nathan in Ship's files (XF An. #3), leech meets him after Inferno (#40), later they meet at the wedding of Jean and Scott (X-Men #2.30)
* Caliban - they were in Morlocks (from before X-Men #179), and both stay with X-Factor after being saved from the Mutant Massacre (Power Pack #27)
* Callisto - his leader in Morlocks (from before X-Men #179)
* Cannonball - their two teams join forces during Inferno (New Mutants #71-73), also meet at the wedding of Jean and Scott (X-Men #2.30)
* Chamber - Leech is adopted by Generation X
* Charles Xavier - both were in the Alley (X-Men #179) but maybe did not exactly meet then, Leech sees a hologram of Xavier (X-Factor An. 33), and they do meet at the wedding of Jean and Scott (#2.30)
* Colossus - both were in the Alley in X-Men #179, but maybe did not exactly meet, the X-Factor trainees also learn of Colossus from Ship's files (XF An. #3)
* Crystal - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Cyclops - first sees Cyclops when hiding in the Alley (X-Factor #10), is adopted by X-Factor after being saved from the Mutant Massacre (Power Pack #27)
* Doctor Doom - *Enemy:* they are antagonists in the FF Family Freakout storyline
* Doctor Druid - X-Factor battle a set of alien fake Avengers (XF #32)
* Doctor Strange - Artie Maddicks projects an image of Doctor Strange during battle (X-Factor #32)
* Domino - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Dragon Man - they are members of Future Foundation
* Emma Frost - Leech is adopted by Generation X
* Forge - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Franklin Richards - Franklin and Power Pack save Leech from the Mutant Massacre (#27) so they become friends (X-Factor An. #2), after Onslaught they are at the birthplace of Beast (X-Men UL #14), and both are in Generation X, later the Future Foundation
* Frenzy - Leech sees her after a battle involving X-Factor and Alliance of Evil (X-Factor #33)
* Gambit - after Onslaught they spend time together at the birthplace of Beast (X-Men UL #14)
* Havok - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Hellcat - the Future Foundation kids are held captive by alternate versions of heroes (Fantastic Four #642)
* Human Torch - both become part of the Fantastic Four extended family
* Human Torch (Android) - Hammond is caretaker of the Future Foundation kids for SHIELD (Fantastic Four #5.5)
* Husk - Leech is adopted by Generation X
* Iceman - first sees Iceman when hiding in the Alley (X-Factor #10), is adopted by X-Factor after being saved from the Mutant Massacre (Power Pack #27)
* Jack Power - they became friends when Power Pack were captured (X-Men #195), and PP save Caliban from the Mutant Massacre (#27)
* Jean Grey - Leech is adopted by X-Factor after being saved from the Mutant Massacre (Power Pack #27)
* Jubilee - they meet at the wedding of Jean and Scott (X-Men #2.30), later Leech is adopted by Generation X
* Julie Power - they became friends when Power Pack were captured (X-Men #195), and PP save Caliban from the Mutant Massacre (#27)
* Katie Power - they became friends when Power Pack were captured (X-Men #195), and PP save Caliban from the Mutant Massacre (#27)
* Loki - the kids in X-Factor talk about Loki several times (XF #17, An. #3)
* Luna Maximoff - they meet at the wedding of Jean and Scott (X-Men #2.30), later both are members of Future Foundation
* Madelyne Pryor - the X-Factor trainees learn about Madelyne in Ship's files (XF An. #3)
* Magik - both were in the Alley (X-Men #179) but maybe did not exactly meet, later the X-Terminators join the attempt to save Illyana in Inferno (New Mutants #71-73)
* Magneto - Dani Moonstar tells the kids about the school and Magneto (New Mutants #74)
* Maximus - they are antagonists in the FF Family Freakout storyline
* Medusa - both live in the Baxter Building as part of the Fantastic Four extended family
* Mirage - their two teams join forces during Inferno (New Mutants #71-73)
* Moira MacTaggert - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Monet (impostor) - Leech is adopted by Generation X
* Mystique - they see each other after a battle between X-Factor and Alliance of Evil (X-Factor #33)
* Nightcrawler - both were in the Alley in X-Men #179, but maybe did not exactly meet then, the X-Factor trainees learn of Nightcrawler from Ship's files (XF An. #3), and they meet at the wedding of Jean and Scott (#2.30)
* Polaris - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Psylocke - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Pyro - they see each other after a battle between X-Factor and Alliance of Evil (X-Factor #33)
* Quicksilver - they fight in Central Park as Quicksilver kidnaps Franklin Richards (X-Factor An. #2), and they meet at the wedding of Jean and Scott (X-Men #2.30)
* Rachel Summers - they maybe met in the Alley when Power Pack were captured (X-Men #195), later they meet at the wedding of Jean and Scott (X-Men #2.30)
* Reed Richards - Leech is with Franklin after his parents "died", later all become part of the Fantastic Four extended family
* Rictor - they were trainees in X-Factor together (from XF #17), and part of X-Terminators
* Rogue - they clashed in the Alley several times (X-Men #179, 195), meet again at the wedding of Jean and Scott (#2.30)
* Sabretooth - *Enemy:* Sabretooth tries to kill him in X-Factor #10
* Scott Lang - both live in the Baxter Building as part of the Fantastic Four extended family
* Shadowcat - they clashed in the Alley in X-Men #179, meet again at the wedding of Jean and Scott (#2.30)
* Shatterstar - they meet at the wedding of Jean and Scott (X-Men #2.30)
* She-Hulk - X-Factor battle a set of alien fake Avengers (XF #32), later both live in the Baxter Building as part of the Fantastic Four extended family
* Siryn - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Skin - Leech is adopted by Generation X
* Spiral - they see each other after a battle between X-Factor and Alliance of Evil (X-Factor #33)
* Storm - they clash in the Alley (X-Men #179), after Onslaught they spend time together at the birthplace of Beast (X-Men UL #14)
* Strong Guy - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Sub-Mariner - the Future Foundation kids watch Namor guide them in the deep sea (Fantastic Four #5.3)
* Sunspot - their two teams join forces during Inferno (New Mutants #71-73), also meet at the wedding of Jean and Scott (X-Men #2.30)
* Susan Richards - Leech is with Franklin after his parents "died", later all become part of the Fantastic Four extended family
* Swordsman - the Future Foundation kids are held captive by alternate versions of heroes (Fantastic Four #642)
* The Thing - both become part of the Fantastic Four extended family
* The Watcher - the entire extended Fantastic Four circus invades Uatu's Moon dwelling (FF #2.13)
* Thor - the kids in X-Factor talk about Iceman being kidnapped (by Loki), probably know about Thor rescuing him (XF #17), also X-Factor battle a set of alien fake Avengers (#32)
* Trish Tilby - Leech sees her reporting outside Angel's memorial (X-Factor #17) and on TV (#20)
* Valeria Richards - both become part of the Fantastic Four extended family
* Valerie Cooper - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Vision - the Future Foundation kids are held captive by alternate versions of heroes (Fantastic Four #642)
* Warlock - their two teams join forces during Inferno (New Mutants #71-73)
* Warpath - they meet at the wedding of Jean and Scott (X-Men #2.30)
* Wizard - *Enemy*: Wizard and Quiet Man imprison the Future Foundation kids (Fantastic Four #642)
* Wolfsbane - their two teams join forces during Inferno (New Mutants #71-73), also meet at the wedding of Jean and Scott (X-Men #2.30)
* Wolverine - they clash in the Alley (X-Men #179)