Not much is known about "Summerboy" - he's a silent nomad that loves freerunning and sightseeing. He tries to visit as many towns as possible, only returning to a select few in order to visit friends and family. Nobody - except his sister, Truffles - knows his real name or even what his voice sounds like.

Summerboy is a very antisocial and private person. He only interacts with others (usually with sign language) when he absolutely needs to, making him an incredibly hard person to befriend. Suffers from RBF despite being generally content. Doesn't like being touched by others. If Summerboy doesn't like interacting with someone, he straight up leaves - regardless of whether or not they were done talking to him. The only people that stick around him are a) those who are comfortable with silence, or b) those who don't mind talking for 2 people.