How I Tame My Valkyrie Harem

[Warning: Adult Content (R18+) - Contains Lemons]Our protagonist transmigrated as Rick into his favorite book, after a reading marathon of that story. His favorite female character, named Sarah, was the first thing he saw.So why is he so sad? Oh, that’s right.BECAUSE HE WILL DIE SOON!Rick is an insignificant Extra with the worst class, who is destined to die early on in the story. His only hope is to steal the power from the MC.He was expecting a cheat combat power, but he received the [Valkyrie Tamer System].Now he will need to form a party of girls, turn them into Valkyries: His loyal underlings with special powers.Rick will train them to level them up, build their powers, and tame them using their lustful desires.Can he face death?