What would you do? Would you believe him?

This girl at my school has been giving me clear signals. I’ve been proactive in introducing myself and engaging with her. She’s very receptive and open to me. This guy who’s in some of her classes randomly implied that she’s his girlfriend but I’ve only seen them together a few times and I haven’t seen anything on her socials that indicates she has a boyfriend.
What would you do? Would you believe him?
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