Mr. Fanservice/Web Original

Jonas Wharton from Lonelygirl15, an orphaned Lonely Rich Kid hero who appears shirtless regularly with little provocation.
Bladezz from The Guild, especially in the music video. In-universe, he's even a model.
The Nostalgia Critic will frequently get shirtless, is a Wholesome Crossdresser occasionally, be the Reluctant Fanservice Boy when he's made to by other people, has given blowjobs to joysticks and is the master of The Immodest Orgasm.
Doug's other character, Ask That Guy With The Glasses, is just as fun. A Depraved Omnisexual who'll "go down on anyone and anything", does porn movies, will give blowjobs to his pipe, doesn't think het incest is kinky enough and practically embodies Evil Is Sexy.
There were three in Suburban Knights; Critic was dressed as Link, with a short tunic, no tights or pants, and the camera focusing heavily on his long, pale legs. Benzaie, who was dressed as Conan the Barbarian, was walking around constantly shirtless and wearing a leather skirt. Jew Wario was dressed as Jareth from Labyrinth and his crotch got so much attention that he ended up weaponizing it in battle.
Daichi Hashimoto from Greek Ninja is unaware of the fact he is.
Evan of Everyman HYBRID oh so much. Not only is he holy-fricking-cow gorgeous, he's a take-charge, compassionate (kind of) Axe Crazy Knife Nut, which only seems to make him hotter. For your consideration: Hot, seeking justice, and batshit insane. Mmmmmm.
The second act of "A Very Potter Musical" gives us a disturbingly handsome Voldemort in nothing but tights, tap shoes, and a cape.