Should I be worried for my younger brothers pleco?

So about 2 months ago I noticed weird stuff growing around the nose of my younger brothers pleco, I've owned several plecos before and never seen this, and I wasn't to worried about it someone told me it means its male, but recently its spread more and I was wondering I'd I should be concerned, he's acting healthy hes active he eats, but it still concerns me none the less! Advice would be welcomed and helpful, thank you so much!
!! EDIT!!
We were able to find out it was a fungus, and the pleco is doing much better after fungi treatment!