Tobio Ikuse/Relationships

Vali Lucifer
Initially, it was said that Vali and Tobio hate one another, but it is was revealed in Volume 19 that Vali seems to share an older brother-younger brother type of relationship with Tobio. In the past, Tobio and Vali lived together, so they know each other quite well. According to Tobio, Vali is very clingy, comparing him to a troublesome little brother, so he avoids seeing him.