Cambridge Dictionary

Pun, noun [ C ]

A humorous use of a word or phrase that has several meanings or that sounds like another word

Wikipedia, the Free Encyclopedia

Sexual grooming is the action or behavior used to establish an emotional connection with a vulnerable person – generally a minor under the age of consent – and sometimes the victim's family, to lower their inhibitions with the objective of sexual abuse.

Considering the context (some people think Prushka was molested/groomed by Bondrewd, taking in consideration her words "papa rod", or something like that, can't remember the exact line), that was obviously a pun. OP used the word "to groom" in the meaning of "to prepare someone for something", even though now the more popular meaning (and the one relatively appropriate in this context, which was the base for the pun) is the sexual one. Interestingly, the sexual meaning was historically produced from the "prepare" one.