Yami-ochi Rasu Bosu Reijou No Osananajimi Ni Tensei Shita. Ore Ga Shindara Bad End Kakutei Na Node Saikyou Ni Natta Kedo, Mou Yami-ochi "yandere-ka" Shitemasen Ka?

I Reincarnated as the Villainess’ Childhood Friend Who Falls into Darkness. If I Die, It’s a Guaranteed Bad End, So I Became the Strongest… But Hasn’t She Already Fallen Into Darkness [and Turned Yandere]?