Tensei Akuma no Saikyou Yuusha Ikusei Keikaku

Low-ranking demon Kakyuu has amassed unparalleled power during his two millennia in hell. But when he gets caught in the cross fire during a battle between gods, he's freed from that cruel life—and banished to another world altogether!! He finally has the peaceful, relaxed life he's longed for, but peace doesn't come easy...especially when the village that took him under its wing is razed to the ground. When he finds Alus, a baby who was left in the ruins of the village, this demon vows to repay his debt of gratitude—by making this baby the happiest child in the world!

(Source: Yen Press)