I have a weird question

So I’ve noticed my boyfriend has strong oniony smell when he sweats under his arms. I’ve never been one with a strong odor I don’t even sweat that much. Never have. I’ve never really gotten musty under my pits. But now I’ve noticed that I’m starting to smell like him. Like for example. Well have sex, that’s when he’s sweating the most and I smell it. Then we take a shower go to sleep. The next morning I’ll smell it in my vagina and pits? Has that ever happened to anyone?