Am I bisexual?

I’ve only ever had romantic feelings for guys, ever since I was a kid, I still remember my first crush and my was he handsome for a 1st grader😂. I’m currently in a year and a half long relationship with a guy, and I’m madly in love, no doubt about it in my mind. But ever since I was a teenager I’ve had a sexual attraction to girls. I’ve never had feelings for a girl or ever had a crush on a girl, but I find myself fantasizing more about girls than guys. I catch myself looking at other girl’s butts or maybe staring a little when they have cleavage exposed. I get off more on the idea of women then men.

It seems that romantically and emotionally, I’m interested in men, but sexually I’m more interested in women? Is that a thing? Does this make me bisexual? I’m pretty sure it does but I’m not completely sure. I’m not feeling confused or bicurious, I just feel indifferent. If I’m bi then I’m bi, it doesn’t change my current relationship or my feelings for him, but I guess I just don’t know what classifies as bisexual, seeing as I don’t find myself having romantic feelings for females