Implicating pegging → toying_partner
Link to implication
Reason:
The definition of pegging on the wiki states that pegging is "A female character wearing a strapon and using the sex toy to engage in anal sex with a receiving male character" and that it specifically only refers to that situation. It already automatically implies anal_penetration, sex_toy, and male.
This definition logically implies female_penetrating, male/female, and toying_partner. Under the given definition, any situation which can be tagged 'pegging' must already be one to which those tags are applicable. Of those, toying_partner is the one least consistently applied to pegging images, and so is probably the best candidate for implication.
Updated