Ano Otome Game wa Oretachi ni Kibishii Sekai desu

After being reborn in the world of an otome game as an insignificant background character, Leon tries his best to lead an uneventful life, but someone else who reincarnated there has a different idea. Marie may be insignificant like Leon for now, but she's intent on slipping into the main character's role and claiming all the love interests for herself! Leon narrowly manages to impede her first attempt, but will this really stop her? Why does he have this sinking feeling that something's gone terribly wrong?!

(Source: Seven Seas Entertainment)