Inko Valentine

Inko Valentine is one of the main antagonists in the Null series and a founder of the Jero Clan. He is the second son of Christina and Clemming Valentine, and is the younger brother of Chris Valentine. He is immensely powerful and during the Heaven No More arc, he kidnaps Clemming to use as bait for a trap that Chris eventually falls into in effort to rescue their father.

Dissolve with the Valentine family
During Inko's late adolescence, he became good friends with Rīkuu, who eventually cast a spell under him which gave him an unfathomable hate for his family and their history. Following this incident, he fled Lua Island with Rīkuu and Time to the Paki Islands. Christina went to search for Inko, and upon finding him, he defeated her and demanded she go home and that if she didn't, he would surely kill her.

A mere year later, Inko, Rīkuu, and Time invaded Jero Island to take for themselves, and sure enough massacred all of the inhabitants; shaping the island into Time's own empire.