Verified answer

It's not a common name, but I think it reads "riu"

理(=ri) is reason, rational, intelligence

宇(=u) is originally a house covered with a big roof. It also means the world covered with a big sky, or sometimes the space.

I'm Japanese but I don't know if this is a boy's name or girl's name.

理 (hiragana: おさむ, romaji: "Osamu") : a male given name

宇 (hiragana: さかい, romaji: "Sakai") : a female given name

"Sakai" can also be a Japanese surname, variously written, most usually with the characters for ‘rice wine (sake)’ and ‘well’.