Post the theme songs of anime/manga/visual novel characters. Most anime characters have some sort of theme song, but you don't really have to post that, just the theme you think is appropriate. If that works that the anime's theme matches perfectly with the one you like, it's all good. Since characters from a manga-only work don't have themes (unless Jojo?) feel free to post appropriate ones.
Template for how to do it -
Kamina from Tengen Toppa Gurren-Lagann:
Although I prefer this as his theme, it's more recognizable and is similar to Simon (Garlock's) theme, which ties into the two being brothers.