 If you liked Mirai Nikki |  ...then you might like Btooom! |
The main characters are both antisocial, and some what of cowards at first. They are forced to play a game and fight for their lives, killing other players in the process. While the female protagonist in Btooom! is not a Yandere, she does give the main character a reason to fight, similar to what Yuuno gives Yuki.
report Recommended by Mythical_Truth