Why would a guy get jealous of my crush if he just wanted sex from me?

he gets so jealous, always speaking bad about the guy i like. they're both the same age and slightly younger than me. even though i've made it obvious i am not attracted to him and we have had a good friendship so far.

he's beginning to send me suggestive texts which i'm sure will turn into openly hitting on me - so i am preparing to distance myself from him. he is still being salty towards my crush.

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+1 y
guys, guys I'm not sleeping with any of them or with anyone! We are part of a 5 people friend group and I like talking to both of them - we have common interests. The guys actually seemed to get along as they're very similar, however they dont talk much anymore. They're both great guys - but I like the one because he just has that special something and cares about me too. so please give an opinion knowing this as well. I should have given these details, sorry about that!
Why would a guy get jealous of my crush if he just wanted sex from me?
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