2,075. Intimacy with a Zavah Who Has Immersed But Is Still Watching
Hilchos Issurei Biah 6:12
If a minor zavah immerses in a mikvah on the night of the day she is watching, or if a major zavah immerses on the seventh night, it is as if she didn’t immerse at all. This is comparable to a niddah who immerses during her seven days.
Hilchos Issurei Biah 6:13
If a man is intimate with a major zavah after she immersed on the seventh day of her counting, or with a minor zavah after she immersed on the day when she she must watch herself, he is not liable for the penalty of kareis (spiritual excision) because she immersed at a time when she was potentially able to immerse for purposes of ritual purity. It’s just that this woman is in a tenuous situation regarding acts of intimacy and things she touches. (This will be explained in the next halacha.)