Yeah, sure there aren't any verses that explicitly tell us not to remove sexual organs, but there are verses against dressing like the opposite gender. Deuteronomy 22:5 says:

"A woman must not wear men’s clothing, nor a man wear women’s clothing, for the LORD your God detests anyone who does this."

The Bible also says that our bodies belong to God, they were bought with a price, so we have to honor God with them and we can't just do whatever we want, even if it feels right.

"knowing this, that our old self was crucified with Him, in order that our body of sin might be done away with, so that we would no longer be slaves to sin;" Romans 6:6