Nao Kusunoki

Nao Kusunoki, originally named Naotora, is the son of a bureaucrat in the Japanese Ministry of Foreign Affairs, and gets forced into an arranged marriage after the crown prince of Urunei, mistaking him for a woman, requests to marry him. His father wants to please Urunei - an important ally to Japan - seeing this as an opportunity to advance his career, and sends Nao to Urunei as his daughter, dressed like a woman, to become the crown princess.

Peringatan Spoiler: Klik Untuk Melihat

By the end of the series, Nao is revealed to be the reincarnation of Putri Harimau, a female tiger spirit from the East who founded Urunei together with the Uruneian royal family's ancestor the dragon god, and has fallen in love with the crown prince.

(Source: Shounen☆Princess volume 1)