In this video, a semi-religious step-mother checks out her step-son's dick that is exposed and hard. She can't help but approach him. She has a small dialogue with herself trying to convince not to touch her step-son, by she does it anyway because it's hard for her to hold back and not do anything when her step-son is "hurting" with such a raging boner. So she pounces on the chance of sucking his cock and eventually bouncing on it and sucking her step-son dry. ;)