No they don't switch. MC wants to switch so he can be on top and make a baby, but ML doesn't want to switch because he likes being the top and and also wants to make a baby.
MC lies about being really good on top in general (even though he's never had sex before with others) and ML says "well it's only fair that I stay in top for a while first before we switch because if you are THAT good then I'll like it too much and I will never get to be the top". MC agrees, but ML doesn't have any real intention of switching and MC keeps forgetting to switch or gets too caught up in the moment and likes the way it feels anyway.

Do they switch? Like during s*x. Are they both versatile?