They're just saying its usually guys who ask girls to dance or what have you and get told they have a boyfriend, so they were a little surprised, not so much complaining.
Yeah sorry this is acceptable coz if his girlfriend saw it could cause problems for him but I shit you not I saw a long lost friend and I was like HEEEEY and the first thing she says uhhh I have a boyfriend she gave me the hand thing and everything then I was like it's me *insert my name here* and she was like oooh I didn't realise...All I said was hey? We don't talk much anymore XD
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