A few years ago, I spent a few nights in a dormitory of a youth hostel in China.
My bed was against the wall. The first evening after I checked in, with the room light on and shining the way it did, I could see cum stains on the wall against my bed. I did not notice it when I moved in that afternoon.
I faced a dilemma. If I pointed it out, the boys might think "the lady doth protest too much" and think I maybe reacting to cover up "my" cum stains. If I said nothing, they might see it and think those were my cum stains.
In the end, I decided to do nothing and thankfully, no one mentioned it either. So all's well that ends well.