Ranma ½ (1989)

S1E10 P-P-P-Chan! He's Good For Nothin'

Unaware that the little black pig is actually Ryoga, Akane takes him in as her new pet, giving him the name P-Chan. This situation frustrates Ranma, who is determined to keep Ryoga away from Akane but feels compelled to keep Ryoga's true identity a secret. The comedic tension escalates as Ranma grapples with his conflicting desires to protect Akane and maintain his honor.