Oriole

Oriole is a traveler of magic and shadow, he's kind and intelligent, but also very nervous. He prefers to keep personal details to himself, as plenty of world travelers do.  

He's good friends with Vivian, and is acquainted with Eclipse (due to them both training in mage class). It's only after he decides to tag along with the gang to take down shadow essences threatening Aster's safety does he properly meet Alex and Cosmo.

Oriole specializes in using magic through runes and, thanks to some tips from Remacis, is capable of making up his own on the fly.