This one requires some explanation.

Back when Yerf! was still in operation, there was an artist who often made fun of Christians, using a cloying pink character, who got nicknamed Pepto. Well,  angelbearoh who is Christian, occasionally drew responding artwork, using the same character. This caused some activity and attention on Yerf! with others joining in, using Pepto in other drawings.

Note that  angelbearoh drew Stargazer's muzzle and stomach light blue instead of the usual white. This was done to emphasize the joke.