Henchmen (PHB)

Henchmen are much that hirelings are not. They are adventurers who serve out of loyalty. They are willing to risk their lives for those they respect. They are also hard to find.
Henchmen are powerful allies to a player character. Unlike hirelings, they have the nerve and ability to become powerful adventurers. Although they expect their share of treasure, they do not usually join a player character for money. They are attracted to the PC because of his reputation or other qualities he possesses. As such, henchmen cannot be expected to flock to the banner of a neophyte adventurer. He may gain himself one or two companions, but others come only when he has earned a greater reputation, met more people, and proven himself a true friend and ally to these NPCs.
Henchmen can come from any source. Most often they are at first mere hirelings or followers who, through distinctive actions, come to the attention of the player character. Some may be higher level, more skilled hirelings who develop a bond to the player character through long employment. Others may be followers who have sound advice for the player character.
A henchman is always of lower level than the PC. Should he ever equal or surpass the PC's level, the henchman leaves forever; it is time for him to try his luck in the real world. In some ways, the player character is the mentor and the henchman his student. When the student has learned as much as the teacher, it is time for him to go out on his own.
Henchmen are more than just loyal followers; they are friends and allies. Naturally, they expect to be treated as such. They have little need for those who do not trust them or treat them coldly. Abusiveness or taking advantage of the friendship quickly ends the relationship. Just as players must with their own friends, player characters must be sensitive to the needs and feelings of their henchmen. Furthermore, henchmen attach themselves to a particular player character, not a group of player characters. Thus it is only under the direst of circumstances that a henchman accepts the orders of another PC. Should his friend (the player character) fall, the henchman sees to his needs. He doesn't abandon him and continue on with the other player characters unless this is clearly the only way to aid his friend.
A PC's Charisma determines the maximum number of henchmen he can have. This is a lifetime limit, not just a maximum possible at any given time. In a world where the fallen can be restored to life, it is expected that a man would make this effort for his dearest friends, both player characters and henchmen. For example, Rupert the half-elf has had seven henchmen, but all have fallen for one reason or another. Rupert's Charisma is 15, so with the death of his latest henchman, no more come to join him. (Word has obviously gotten around that Rupert's friends tend to meet unpleasant ends, and he doesn't even have the decency to bring them back to life! Even if he had tried to raise his henchmen and failed, Rupert would still be viewed as a jinx, bad luck for those around him.)
Attracting a henchman is fairly difficult. One cannot advertise for friends with any great success. They grow and develop from other relationships. A henchman can be found by placing trust in a skilled hireling. Heroic deeds (saving the life of an NPC) can create a strong and instant bond. Love certainly can form this bond. The player and the DM must trust their own judgment to determine when an NPC becomes a henchman. There is no clear line an NPC must cross to make the transition from hireling to henchman. Instead, it is a slide from one status to the other.
Once an NPC becomes a henchman, the player gains a high degree of control over the character. He should be responsible for the record keeping for that character. It is almost, but not quite, like having a new PC for the player. If the DM allows it, the player can have all information regarding the abilities of the henchman, although the DM may choose not to reveal this information. The player is allowed to make nearly all decisions for the NPC, but the DM can overrule any action as being out of character.
There are certain things henchmen do not do. They do not give away or loan out magical items. They do not allow others free access to their spell books. They do not tolerate spell use that questions their loyalty (detect lie or know alignment cast upon them). They do not accept less than their due share. In general, within these limits, henchmen do what is desired of them. The DM can at any time dictate the actions of a henchman, since the character is still an NPC.
If a PC is not attentive to the wishes and needs of his henchmen, or if he abuses and humiliates them, he can expect the worst. This is the stuff mutinies and rebellions are made of. Should an abusive player character fall at the hands of a once-loyal henchman, he has only himself to blame.
On the other hand, not all henchmen are paragons of loyalty. The player character must always be aware that henchmen are sometimes not what they seem. They can be a means to get at the player character. Throughout history, many a cruel and cunning villain has posed as a true companion, waiting for his chance to strike or spy on his friend.