In Honkai Star Rail fanart or video; Caelus aka Male Trailblazer is an idiot, fan of trash can, harem king, etc. If Firefly saw Caelus with other girls; she would be very angry [in cute style] jealous, possessive, and transform into Sam chasing Caelus.
You know that Firefly is jealous and possessive waifu in Honkai Star Rail.
But in Bonds of Stars; Y/n aka Kurosawa Raito is much different like Caelus. He is introvert due to his past, reluctant, cool, quite level headed, OP. He also the only person who can argued or quarrel with Firefly much like husband-wife/married couple. I could imagine, he can block or counter Firefly when she transformed into Sam using his Dunamist power or transformed into Ultraman Next/Nexus in sam size or slightly taller than Sam.