|Born||Seán William McLoughlin|
|Birthdate||February 7, 1990|
|Occupation||Video game commentator|
|Years active||2007 - Present|
Seán William McLoughlin, better known by his online pseudonym JackSepticEye or simply Jack, is an Irish YouTuber and one of Markiplier's best friends. He and Mark have some collaboration videos together. He has played in Co-op Quartet with Mark, Wade and Bob.
Jack and Mark first met on Twitter, where Mark had found his channel and private messaged him to start a conversation. Despite the fact that Mark was the first one to make a move, Jack had actually been a huge fan of Mark long before, and basically started his whole channel because of him. He says that he admires the way that Mark made YouTube about the fans and not the numbers, and he follows that code just as much as he would. Even now, after an entire year of knowing him, Jack still says that he looks up to Mark dearly and respects and cares about him greatly. Their very first collaboration video was published on April 25th, 2014.
Jack and Mark have played Garry's Mod Sandbox together, one time with PewDiePie. The "Gmod Sandbox w/ JackSepticEye" video was their first collab video ever. At first Jack tried seriously to do something, but after constant Mark's interference's, he accepted to participate in rocket launches. At Prop Hunt with Jack usually plays in same team as Mark and follows his instructions.
While Jack and Mark were playing The Forest. Jack has confirmed that he is immune to Mark's provoking and stated that it is impossible to offend the Irish. Their ship name, Septiplier, was joked about.
Jack is one of the players in Mark's Grand Theft Auto V gameplay series. He managed to get a jet at one point and even accidentally shot down Mark in his helicopter. He crashed his jet during the most recent episode. Wade also killed Jack in the series and made Jack's body fly in the air with an SUV.
Mark has photoshopped Jack to make him a leprechaun on a Happy Wheels Billy. In one of Jack's videos, Mark along with Jack and two other people, played Cards Against Humanity. He's also a guest on the Five Nights at Freddy's Gmod maps as well.
- Main article: Seán McLoughlin/Photos
- Jack's signature "top of the mornin' to ya laddies" phrase was inspired by Monica Geller's Irish impression from Friends. The slap came later on and he incorporated it into his intro.
- Jack now has more than 13 million subscribers, making him not just the most subscribed in featured channels, but also in Ireland.
- Jack is the only one of the main friends who wasn't involved in the Drunk Minecraft series.
- Jack also has more than 1 billion video views.
- Jack is 5 feet 10 inches, same as Mark.
- In a fan-made game, Jackventure, Jack imitated Mark by using the Wilford Warfstache voice.
- Whenever Mark tries to impersonate Jack, Mark uses a Scottish accent instead of an Irish accent.
- Jack was originally supposed to appear in an episode of Drunk Minecraft but was canceled following an incident with Mark being told not to drink ever again leading to the series' cancellation.
|Relatives||Mark Fischbach | Tom | Mom | Dee | Chica|
|Aaron Ash | Amy Nelson | Bob Muyskens | Cyndago (Daniel Kyre • Matt Watson • Ryan Magee) | Ethan Nestor | Kathryn Knutsen | Sean McLoughlin | Tyler Scheid | Wade Barnes|
|Recurring Collaborators||Brooke Lawson | CinnamonToastKen | Cryaotic | EatMyDiction1 | Fine Brothers | Game Grumps | Jesse Busemeyer | Jordan Maron | Latin Goddess | LixianTV | Matthias | PewDiePie | Rosanna Pansino | SeaNanners | TheRPGMinx | Zombiemold | Ohmwrecker|
|Others||Jessica Fossey | Caspie1405 | Coyotemation | Cranbersher | Crown Interactive | Darkiplier | DidYouKnowGaming? | Dlive | Edge | Hot Pepper Gaming | jacksfilms | JeffKyler14 | markiplierSINGSbadly | MatPat | Octobarian | Polaris | RadicalSoda | Random Encounters | shodleech | Sienna Spalding | SuperMega | Tiny Box Tim | Tobygames | Triggerhappy1337 | UberHaxorNova | Wilford Warfstache|