Fat build up at base of tail or something else?

[Jay3479]

good afternoon everyone!!! I've noticed in the past week that Freddie has a bulge at the base of his tail he's been growing quick n eating a ton now in the past with some species of reptiles this could b a food storage like leopard geckos n bearded dragons I'm just wondering if I should b concerned or not? Could it b a sperm build up? Or just the way they r? Thanks in advance if needed I can post another pic or 2 thanks
Jay

 

[Damicofam6]

Just means you cham is a boy.

 

[Chameleon Mike]

Boy parts

 

[Jay3479]

Ok cool thanks so nothing to b concerned about a week ago was not even there how old do u guys think he is cause I think I found a sperm plug yesterday but wasn't sure it was stuck to 1 of the pieces of wood walk ways