The Mishima and Satoda families have yet to make a 'betrothal' agreement. After both sets of parents passed away, 'Karen,' who is learning to be a bride at the Satoda household, notices that her betrothed, Ryota, has awakened to his sexuality. Ryota gets flustered just looking at Karen's huge breasts. Seeing him like this, Karen feels both endearment and pity, and she starts taking away the firsts of this clueless boy one after another, getting hooked on the sensation...
