Beelzebub - Season 1 Episode 5

After a sleep deprived night, Oga notices he has a strange mark on his hand, revealed to be Zebel Spell, a symbol of the contract between him and Beelzebub. Hildegarde and Alaindelon explain that a Demon Lord's parent is a vessel for his power, and the mark will grow the more opponents Oga defeats. Wanting to get rid of the mark, Oga decides to give up fighting in the hopes it'll make the mark smaller. Meanwhile, another delinquent, Tatsuya Himekawa, hires some thugs to kidnap Hildegarde and Takayuki in order to get Oga's attention. Oga uses Alaindelon to sneak in and forgoes his promise to beat Tatsuya's henchmen. Tatsuya goads Oga into hitting a cermanic plate hidden under his shirt, but his punch is so powerful it knocks him out anyway. Tatsuya then tries using a stun rod, but Oga resists it and uses Beelzebub's power to beat him, which in turn makes his mark larger.