"Dark Heaven" Couple with reversible roles

I’d like to recommend a comic called Dark Heaven; it is truly moving. It deals with themes such as childhood love, the world of rock stars and the price of fame, as well as racial discrimination and homophobia in the US a few years back. It is a beautiful, profound story that I believe is not very well known. In it, the sexual roles (top/bottom) of the main couple switch on several occasions—something I haven't really found elsewhere in the BL genre. Do you know of any other BL manhwa or manga where the couple's roles—top and bottom—switch at least once? I’m a woman, and I wonder if those roles are always so clearly defined in real-life relationships between men.