Child Soldier: Red Star was originally just some kid enlisted in the Security Force. He was then picked as a test subject to create the perfect Super Soldier. The experiment had Gone Horribly Right.
Clear Their Name: The Titans were summoned to stop a monster which they initially assume is Red Star.
The Heart: Starfire. She convinces Red Star to help people and stand up for himself and tells off his old superior when he tries to blame Red Star for the monster and gets him to listen to her.
Heroic Sacrifice: Red Star destroys the monster but releases way too much energy in doing so. Starfire has to take him into the stratosphere so he overload without harming anyone.
Platonic Life Partners: Red Star and Starfire establish this sort of bond over the episode.
Power Incontinence: Red Star has to discharge nuclear energy every few hours or he overloads which is why he isolates himself. Unfortunately his isolation becomes a moot point when it's pointed out that even though he contains himself so that no one around will get hurt, the runoff from his energy releases escapes out into the environment.