"Wowee! That Sim is irresistible! Amelia has a major crush on Ash!"

Crushes are a new thing in High School Years. And do you have any mods? Especially the wonderful whims mod? Because that mod will trigger that kind of stuff. But I do know that my teen Sims have had random crushes on people that I didn't even do a thing about either. If you don't want it to happen you can click on your Sim and there's an option to get over crush.

Crushes can happen by random, but flirting can trigger it too. I had a sim meet a boy, and without any interactions (or it was just simple greetings, if any), bang, she has a crush. When you click on your sim, there’s a couple of interactions about their crush. You can try to get over them, write in a journal about crush, or think about crush, and sometimes you get moodles when around them.