Oreryu is a serpentine, blue dragon, with grey scales going down his chest and grey spines along his body. He has two arms, and is usually gesturing at himself with his thumbs. On the back of his head are three black horns, and he wears a lavender headband. Oreryu's eyes are almost always shut, and for some reason, his mouth seems sewn together, though he can still talk normally.
Oreryu is very self-centered, and believes people should put themselves first. Despite his self-centered nature, though, Oreryu is very willing to help people, in his own special way.
Oreryu causes people to act without concern for anyone but themselves. This can actually be a good thing, as Oreryu's influence can cause people to find their own certain style without worrying what others think. But oftentimes, those inspirited by Oreryu will come across as weird and/or annoying due to how aggravatingly self-sure and cocky those Inspirited by him become.
Yo-kai Watch animation series
In EP141, Nate discovers Oreryu inspiriting Bear, Eddie and Katie, causing them to do strange things (such as making Bear carry around conflicting sports equipment, or Katie wear their backpack around her waist). When confronted, Oreryu explains that he makes people act without concern for other's opinions, and that with his help, many notable people found their unique styles. Hearing this, Nate decides to have Oreryu help him stand out more. But while inspirited by Oreryu, Nate ends up annoying everyone around him, especially his mother. Eventually, Nate's mom gets so mad that her rage manifests as a dragon, which eats Oreryu and puts an end to Nate's plan.
However, he was resurrected in the Recap Time, as well as seeing that Nate befriended him and had his medal.
"Oreryu" is a visual pun on "my style" (Japanese: 俺流,Ore ryū, "my own way"), with the last kanji being a homophonic pun on "dragon" (Japanese: 竜,Ryū).