Speedster

Speedster is a local superhero with super-speed powers. He has been a superhero for almost a year, and pretty much everyone loves him. However, in that year, he still hasn't decided on a name, so the public has taken on calling him "Speedster" for now.

Thin Air
Thin Air is a fellow superhero that is seen working with Speedster not only to fight villains, but to figure out what they are up to. Speedster has been a superhero for a little longer than Thin Air, and the public are more used to seeing him around (as Thin Air isn't exactly easy to see). Thin Air seems to be the more serious of the two, but that doesn't mean Speedster doesn't take his responsibilities seriously. (It just means he likes having fun too lol)

Jessica Keeper
He saved Jessica from falling building debris in Episode 1. Later, in Episode 5 he sees Jessica at a park while he is getting ice cream, and invites her to join him. They chat for a while, and seem to be on friendly terms.

Alexa Johnston
He saved Alexa from building debris.

A.I.
Speedster seemed excited to ask A.I. (Thin Air's invisible assistant) to look through databases for information on villains' weapons.

Villain 1 and Villain 2
Speedster and Thin Air defeated these villains in Episode 4 and wondered at the origin of their glowing weapons.