Frustrated married woman Mako was hoping to be cuckolded in the kotatsu!? Those in a forbidden relationship that must never cross the line engage in taboo acts in the kotatsu. Some are in a position where they cannot refuse their partner, some get excited in such a situation even though they know it is wrong, and some have a sense of chastity that it would be bad if their husbands found out... They are violated in the blind spot of the kotatsu!