when you hide in a room when two people are having sex. Then when they are about to cum you jump out on them. And cum all over them yelling segulling....
to cum into your hand then chuck it at someone, like bird shit
also, if a couple are dogging, or just having sex in a car you wank onto the car so it looks like birds have shit on the car
When a group of two or more men stumble upon a drunk or otherwise incapacitated female and descend upon her in order to sexually assault or rape her, much like seagulls flock and dive to the surface for scraps of food.
A group of three men found a woman passed out in a dark alley with no one around and decided they were going to begin seagulling her by taking turns.