I feel like Yves' and Luca's salvation endings in Virche are pretty much this "merry bad end". To an extent maybe Mathis' despair ending too? This last one was my favorite out of all those bad endings tbh.
I think this type of ending is great too!! And now that I think about it, Orlok's Normal/"Good" ending in Piofiore Fated Memories also fits? After all, while they technically run away together they'll pretty much spend the rest of their lives running and hiding from Dante, who is still alive and very much intent on killing them both... Or well kinda worse depending on how you see his actions in the bad ending. I personally would've loved to see a sequel to this ending instead of the one we got in episodio 1926.