Why is his reply different to when being asked if we are dating?

[female13]

So my friend and I like to bicker and tease each other often, at the same time he seems to get annoyed with me easily and distant. When we are out we get asked if we are dating, to which we both put a lot of emphasis on it and are like Nooo!, we also get asked if we are siblings sometimes too which we reply no that would be weird, as we have slept together once over a year ago, (he didn’t want to do it again and I had feelings for him which have decreased) but he feels the need to explain why especially if it’s with a guy I’ve been flirting with…

last night we were out and someone asked him and our friend if they were together, which they both replied calmly ‘no, just friends’. Why does he have to be dramatic with me when asked that question? But calmer with her?

[spartan55]

I think you are seeing things this way because you aren't friends

[female13]

But we are or at least I thought we were

[female13]

What would you say we are? Haha

[spartan55]

If people you spend time with are making comments like that everyone assumes. Friends don't have sex with each other either.

[female13]

Those making comments are random people we meet on nights out, that don’t know our background 😂 but okay we are not friends? Thanks for the reply

[spartan55]

They don't have to know you or your history... they see how you act together. Nice try though.

[female13]

If we aren’t friends than what are we? Hahaha you’ve officially confused me

[knallpilz]

This might be long shot, but it's possible that he has trouble emotionally connecting. Which happens when you have sex with someone you care for. Which might have scared him.
That said, I don't know him. He's showing symptoms, though. :)