There isn't anything that all men love, but fellatio having the penis licked, sucked or kissed comes close.
Most men have their fellatio preferences and dislikes.
Generally, they love when their partner is enthusiastic, relaxed and knowledgeable. As with other kinds of sex, men dislike fellatio when a partner is too rough, too gentle, inattentive to feedback or seems bored or resentful. There isn't anything inherently dirty about a penis, especially after a shower. Feel free to pause or rest during fellatio, and to talk or cuddle if you like. Meds could be ruining your sex life.