Retsu Seiba

Retsu is one of the two title characters. He is a fifth-grade student who is 11 years old, and Go's older brother. Although he is able to control his patience better than his brother, he still lets out his annoyance with someone once in a while. Together with Go, they are known as the "Let's Go Brothers". In WGP, he is the captain of the TRF Victorys. He likes to collect postcards.