To whom does "Nefesh" refer?
Targum Yonasan: It refers to a Kohen who is forbidden to eat Terumah after touching any of the above Teme'im until he immerses in a Mikvah and waits until nightfall. 1
What does "Bo" refer to?
Rashi: It refers to any one of the Teme'im listed in the previous two Pesukim.