The comic isn't supposed to be outright porn. (Or, I at least hope it isn't. That would be some seriously disappointing porn.) The focus of the comic isn't sex, it's a comic about shiny Pokemon. For the frustration of the main character to matter, we should sympathize with her similarly to the way we would with a real person. If you read/watch a story and view all the characters as meaningless fake people, you're likely not reading/watching a very good story.

I apologize for using a buzzword, but it was the best fit for the idea I was thinking of. When the character is drawn so sexually in an otherwise non-sexual comic, it generally communicates that the character is primarily sexual. It says "Look at these frustrated breasts" more than "Look at this frustrated representation of a human being." That's the idea I was trying to get at. The words 'sex object' was the most concise way to the heart of the idea.

If it matters at all, I would be just as annoyed if the character was a sexualized male. Either way, I would consider it detrimental.

It's okay if you like breasts. Tons of people out there think breasts are great, there's nothing wrong with breasts. You want to see breasts? There is porn for that. There is so, so much porn for that. However, in a comic with a non-sexual subject, I don't feel that so much sexualization is needed. In fact, seeing as it shift's the focus away from the comic's main subject, I would call it outright counterproductive.