YOSHITSUNE: Ushiwakamaru to Shizu Yuukyuu no Ai no Monogatari

At the end of the Heian period (794-1185), when the Taira clan wielded power, Minamoto no Yoshitsune, known as Ushiwakamaru, met the love of his life, Shizuka, at the age of seven. Fate tears them apart, and they vow to be together in the future. To protect Shizuka, Yoshitsune goes off to battle, but Taira no Tomomori waits for him, and a woman uses her power as a shield to come on to him with her body...

(Source: Mecha Comics, translated)