I'll start with four manga series:
Otherworldly Munchkin - Let's Speedrun the Dungeon with Only 1 HP! (tabletop RPG-like world, anti-hero protagonist, action)
The protag was cursed by the goddess of a tabletop RPG-like world, so he only got 1HP. But who cares? He stole her worldbook and is willing to exploit the rules as much as possible, while looking for his sister. He got guts and it's fun to see how he exploits game knowledge, foes, and even friends.
The One Within the Villainess (otome game story, villainess protag, revenge)
Emi reincarnates as the villainess of an otome game, but the original soul of the villainess Remilia is still there, watching Emi from the inside, and Remilia can't help but feel genuinely attached to the Emi unwillingly snatching her body. And then, when the condemnation event happens, and Emi tilts, Remilia takes control over her body again... only to promise to take revenge on everybody who hurt Emi.
Tired of all those marshmallow villainesses? Then Remilia is for you; she might not be evil but she's certainly not soft. And for those who don't mind spoilers, here's the scene that "sold" me the series:
Ch6 dialogue
Villager A Wants to Save The Villainess no Matter What! (otome game world with male MC, romance and adventure)
He's born in the slums of the otome game that his sister forced him to play, and the only decent character of the story is the villainess. He then decides to save her from the tragic fate awaiting her at the end of the game.
The series has plenty comedy moments but this doesn't detract from its overall serious tone. Both the MC and the female love interest are likeable characters, the romance moves in a nice pace, and it's fun to see the MC working to get a better life, from cleaning sewers to his first adventurer odd jobs. Make sure to check the light novel too.
Isekai Shikkaku aka No Longer Allowed in Another World
Swords-and-magic world with no game elements, weird protag, comedy.
The protag is a writer from the 1940s who gets into isekai by trying a double suicide with his lover. And he still wants to die, even in isekai. A image is worth a thousand words:
Ch1
