Review Detail of Mii in Grandpa Universe In Multiverse [COMPLETE]

Actually I don't like OP character that much, but it was better than harems. I don't know why people like harem so much. I mean, okay you can get a girl in each world, but could you just get one, not two or more (or worse, all female character in that world)? You indirectly destroy the world, you know. Thats why I like this story. Its balanced between adventure, romance and comedy. The mc is a loyal man, kind and cool. I hope I have a grandpa like him, lol.