Oh i know what you're talking about! It's in ADW: Gacha Date, correct?
I'm also quite baffled by that fact if i'm being completely honest.
I'm grateful coffeedripstudios replied with a general size comparison, so i could better imagine their height!
Here is my interpretation based on the explanation...
(I purposefully avoided putting Jonas and Eve since they're not implemented yet, sorry)
Anyways, i got the quip when i was travelling to the Scattered Forest, there will be an option that says 'You must get warm in all that armor'
That's the one! Choose that and you'll have Ruwin lift you up!