Is this just how teenage boys act?

I have my kids full time at the moment because my husband is a truck driver. Including my step children. I'm very close with them. They call me Momma and their biological mom they call mom. But she hasn't seen them in a few months so they're living here.

I saw on my step son's phone that he was texting his friend and there was a sexual joke they made but I can't tell if it was just normal teenage boys making sex jokes or if this warrants a sex talk about sex with the same sex. I'm not sure. The conversation was my step son sent him a picture of our cat. We've had this cat 3 years. He hates everyone. He will attack you for no reason. He sat on my step son and cuddled on him. He told him "Had him for 3 years and he finally sat on me." One of his male friends said "Wouldn't take me 3 years 😏". My step son's reply was "Straight to horny jail🤣." This could just be 2 close male friends joking. I've already had a talk with my stepdad daughter. She got her first period. My husband thinks they could have just been joking but he trusts me to talk to his kids if I feel I need to.

I have all girls and my step son is the first teenage boy I've ever had so I know they can weird. Does this warrant a sex talk or just let the boys be boys and joke around?

@Kimberly haha I don't think the joke involved the cat. How I took the joke is it wouldn't take him 3 months to sit on my step son.