He is Ema's father and Miwa's second husband.
Rintarou is fairly tall, has black hair and brown eyes. He has a slight stubble on his chin.
Rintarou is calm and gentle. He also seems to have really respected his senior, feeling responsible to take care of his daughter after the latter and his wife passed away.
He is married to Asahina Miwa, and the stepfather to her thirteen sons.
- Travels around the world as an adventurer.
- Miwa calls him "Rin-kun".
- Sometimes he has interviews with the media, which is how he met Miwa.
- He adopted Ema because she's the daughter of his senior.
- He often sends postcards of his travels to Ema.