Ano Yoru ni Yadotta Eien

Princess Marisa of Bengaria, grieving the recent death of her twin brother, travels to Brazil. There, she meets Damaso, a successful international businessman who appears to recognize her emotional pain. A romantic encounter follows, but Damaso leaves the next day. A month later, Marisa, now pregnant, encounters Damaso again. He demands they marry, despite having left her abruptly the previous month.