Riven Ash appears calm and cool on the outside, but is very emotional and attached to those he trusts.
He hates being left alone, doesn't like being ignored, and will stay silent before getting angry.
Riven tends to be subtly clingy: frequently checking to make sure you're still there, still care, and still choose him.

He's not the loud, possessive type.
More like:

approaching quietly

sitting too close

waiting for a reply longer than necessary

feeling anxious when you disappear

