reika's manga / #harem(28)

Demon King makes an agreement with Hero to resurrect thousands of years later. Now 2000 yrs later, he is born and immediately uses magic to ages himself from an infant to a child. Goes to demon school later to entertain himself.

MC and his classmates are teleported into a different world to become heroes and save that world with the promise to bring them back to Earth after accomplishing this. MC, who is declared to be the weakest with creation magic, is betrayed by someone during a dungeon exploration and almost killed but ends up surviving and becomes super OP.

MC's step mom and step sisters as well as MC are teleported into another world and are immediately surrounded by enemies. The priestess who summoned them blew herself up in order to protect them. The MC sacrifices parts of his body to make contracts with spirits to grant him power to protect that world and most importantly his family. Also his dad is a marriage swindler and taught MC techniques to pleasure women.