>>31074591A multitude of reasons.
The most obvious one is that female protagonists are more popular. Going by Danbooru numbers, because I found it easier to use than Pixiv, 28% of Moon images are with Lillie. Compare that to Sun, who has 21%, and you can see the difference isn't that big.
Another thing I noticed, but this time on Pixiv, was that literally all of LilliexMoon art comes from well-established yuri artists. People who regularly draw yuri. There's a reason for them to draw Moon, but no one really has one to draw Sun.
Either way, LilliexMoon is getting more images. Those are two simple reasons that can explain why, though no one would know for sure. I say just take the anon's advice, and don't question it. Just enjoy it.
