Question: Which Greek-American actor portrayed a fictional character on NBC's Days of Our Lives?

<P0-S0> Kristen DiMera is a fictional character from the American NBC Daytime soap opera "Days of Our Lives", portrayed by Eileen Davidson. <P0-S1>  Davidson joined the cast of "Days of Our Lives" in 1993, and departed in 1998 after a five-year stint. <P0-S2>  After a 14-year absence, Davidson returned to the role of Kristen in the fall of 2012. <P0-S3>  Kristen and her brother Peter were raised but not legally adopted by super villain Stefano DiMera at a very young age following the deaths of their parents; however, their mother Rachel was later revealed to be alive. <P0-S4>  Davidson's performance has been met with critical acclaim, having earned herself Daytime Emmy Awards and Soap Opera Digest Awards wins and nominations. <P0-S5>  Davidson departed the series again in 2013, returning on July 28, 2014, for a twelve-week stint which concluded on November 6, 2014. <P0-S6>  Kristen returned once again for another stint that ran from April 14, 2015, to April 30, 2015. <SEP> <P1-S0> John Anthony Aniston (born Giannis Anastasakis; Greek: Γιάννης Αναστασάκης; July 24, 1933) is a Greek-American actor. <P1-S1>  He is best known for his role as Victor Kiriakis on the NBC daytime drama series "Days of Our Lives", which he originated in July 1985 and has played continually since then. <P1-S2>  He is the father of actress Jennifer Aniston. <SEP> <P2-S0> John Black is a fictional character from "Days of Our Lives", an American soap opera on the NBC network. <P2-S1>  He has been played by actor Drake Hogestyn since 1986, with a break in between from January 2009 to September 2011. <P2-S2>  John was created by script writers Sheri Anderson, Thom Racina and Leah Laiman as The Pawn in 1985 and introduced by executive producers Betty Corday and Al Rabin. <P2-S3>  John becomes one of "Days of Our Lives' " most popular characters when he is revealed to be the presumed dead Roman Brady (Wayne Northrop) with plastic surgery and amnesia. <P2-S4>  However, Northrop's return in 1991 led to Hogestyn's Roman being retconned into the entirely separate character of John Black, which also establishes the supercouple pairing of John and Marlena, due to John's affair with Roman's wife, Marlena Evans (Deidre Hall). <P2-S5>  During the time in which he believes he is Roman, John picks up the mantle of Roman's feud with the notorious international criminal Stefano DiMera (Joseph Mascolo). <P2-S6>  John and Stefano's feud is central to the character's history as Stefano is partly responsible for John's memory loss. <P2-S7>  Their lives are further intertwined in 2008 when the two are falsely led to believe they are half brothers—a story that was later disproved. <P2-S8>  Hogestyn's portrayal has made him one of daytime's most popular and recognizable stars. <P2-S9>  Hogestyn was attributed with helping the series out of its ratings slump in the 1980s. <P2-S10>  He was often featured in soap opera magazines such as "Soap Opera Digest" and "Soap Opera Weekly". <SEP> <P3-S0> Victor Kiriakis is a fictional character on NBC's "Days of Our Lives". <P3-S1>  The role has been portrayed by John Aniston since 1985. <P3-S2>  His time on the show has been since 1985 with a brief storyline driven absence in 2004 when his character was "killed off" but found alive on the island of Melaswen.