Kanranee
RAD is having a party to celebrate the end of Comet Hunter Festival, but despite attending the party, Satan still keeps his distance from other students out of guilt for almost ruining that said festival and throwing the entire student body into panic. Little does he know that a certain human exchange student has a different view of that particular event.
This story is set directly after the event 'A Star For You', so beware of spoilers.
[SPOILER ALERT]
The event's story is about RAD's Comet Hunter Festival where students are competing to collect the stars of gratitude by having someone feeling gratitude towards them (basically they have to be kind and help each other). So, in this event gratitude is represented by stars, which appears as twinkles in the eyes of someone who receive them. In the locked key chapter, Satan got so mad at his brothers and almost destroy RAD because they keep bothering MC to team up with them since MC have the most stars among the students.