TUA Universe Mysteries: Darmsy's Age

This is a TUA Universe mystery that relates to Darmsy's age.

The mystery itself.
What is Darmsy's age? The age 18/19 is a fan made one. Some people say he might be 12, some claim he's 30. It's actually quite shocking how many side characters have confirmed ages but Darmsy doesn't.

Theory responses.
As of right now, there have been no theory responses as to what Darmsy's age is.