Context: a boy shouts 「ちはース」 after seeing that a fan club for a boxer has only female members. He is happy to discover this since he is the kind of guy that always tries to flirt with pretty girls.
I understand that this is an exclamation expressing surprise, but is it common? Does it have an exact meaning or it is only onomatopoeic?
Also, is it vulgar? Something like "holy shit", or is it more similar to "wow"? I am asking this because the character shouting it often speaks in a vulgar way.
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