Guys, An old friend is possibly flirting, but I don't know... guys, some feedback please?

A guy I've known for years now suddenly chose to take a class with me and to transition from social media DM to regular texting today. When he spotted me he couldn't stop smiling and talking to everyone about how "WE" are leaving together, walking to a spot together, shopping together, taking this new class now... I thought he was just being goofy, but he's been texting me all day.

He's a nice guy, and we'd actually be super compatible, but tbh I always thought he had a girlfriend, so I'm not sure what's going on rn.

Guys, some feedback here?

Updates
11 mo
@spartan55 what’re you talking about? YES if he’s suddenly flirting after years like that HE should mention there’s been some kind of change on his side. There’s NO reason or motivation for me to rock the boat. Nowadays guys are careless and women get nasty. Are you living under a rock or something?
Updates
11 mo
The bots are clearly on crack to give @Spartan55 "Superb Opinion. @girlsaskguys why allow toxic trolls like this loose?
Guys, An old friend is possibly flirting, but I don't know... guys, some feedback please?
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