Cas sighs
Cas: HEY! I-I'm sorry for being an ass to you...let's start over.
Cas: ...I'm Cassius...Cas for short...um what-what's your name...?
Cas: ...Pft-ok ok I'm really sorry but Serenity!?
Cas: Yeah, that makes sense...
Cas: Yeah...don't know who chose my name either...probably the orphanage owner...stupid old crone...
