obsexed
When someone is so obsessed with having sex with a person they can't think about anything else. Their brain is like a cocky middle schooler.
I saw my crush in the gym. I got a boner and started lifting weights like a beast.
I saw my crush wearing a hat. I thought it was a sexual act. I got a boner.
I saw my crush eating cereal. I thought it was a romantic gesture. I got a boner.