For those who don't care about being spoiled.
No they are not dating or are in love with each other, they are both starring in a movie playing as their parents, Aqua is playing as his dad and Ruby is playing as her mom, and there is a scene in which they have to kiss. Is it weird and creepy? Yes but because it's a movie that they are doing and they are just acting, it gets this weird pass.
Ruby is a bit weird and teases Aqua about the kissing scene, Aqua on the other hand does not like kissing scene and wanted to avoid it but unfortunately he can't.