Mulan was called to the war again as a replacement for her dad....

During the battle with the enemies, her period came and stained her pants.... she was eventually overwhelmed by the exhaustion and fainted.....

When she came to, she was in the sick bay and the medic was attending to her.

Mulan: Wad happened, why am i here?

Medic: oooo u were in the battle and we found u fainted amongst the corpse... unfortunately....ermmm....they...they....they.... sliced off ur dic and your pants was badly stained with blood.....

Mulan: (thinking to herself) phew.... luckily they din find out i am a girl.....

Medic: ...... but you were lucky we found a replacement and stitched it back for ya.......