It's a Showdown, I Have a Power Leveler

On this day: Gu Xiaowu discovered that he and anime characters could interpenetrate their souls. The first character whose souls intertwined was Uchiha Madara. The second character whose souls interpenetrate is Whitebeard. The third character whose souls interpenetrate is Ryuguin Seiya. The fourth one, wait... Gu Xiaowu's face was ashen, why were all the souls intertwined with his men? Isn't there a girl? It wasn't until the day of doomsday that Gu Xiaowu discovered... Also known as Big Brother, help me practice my trumpet. The secret among men. My harem is invincible. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.