Ok kiddo, let's talk about trespass for mesne profits. Basically, it's when someone goes onto someone else's property without permission and then they stay there for a long time and use the property without paying for it. It's kind of like if you went to your friend's house and then you stayed there for a really long time and used their toys and didn't leave when they told you to go home. That would be kinda rude, right?
Well, in grown-up land, trespass for mesne profits is against the law. If someone does this, the owner of the property can take them to court and ask for money to make up for all the time the person used their property without permission. It's basically like the owner is saying, "Hey, you can't just come onto my property and use it like it's yours. You need to pay for that!"
So, remember to always ask for permission before going onto someone else's property and definitely don't stay there for a long time without their permission or you could get in trouble!