It came from the art for battle bunny riven.
Zac is directly below her staring at her
Yes, interactions happen.
Taric was running around with Lux in Pool Party Leona's background.
Warwick wears Urf in a skin, yet, Corki rides on him and Fizz summons him, in some of their skins. But yet, Butcher Urgot is in possession of the body.
Pool Party Lee Sin is interacting with Nidalee.
Going back to Battlebunny Riven. Swain and Talon are also easily visible and have their attention focused on Riven.
He's also not directly below her.