Is it possible for a non-MonoBehaviour class to use built-in functions?

Hey, just as the title says, my question is if non-MonoBehaviour classes that have the ability to be used as var myVariable : MyClass = new MyClass(“foo”); can use built-in functions such as OnMouseOver(). I’m assuming the answer is no, because they can’t be added onto a GameObject and thus don’t have access to colliders of GameObjects

You can see in the docs that it’s MonoBehaviour.OnMouseOver. And you’re correct, OnMouseOver requires a collider to operate, since it uses raycasting (except for GUIElement objects).