There is only one here that I'm pretty sure like no one ships so yay (based on google some I haven't searched yet on it)
Reaper x Blueberry (don't judge me)
Cross x Blueberry

Killer x Blueberry

Horror x Blueberry

Lust x Blueberry (I think some people ship this but I haven't looked it up)

Ink x Nightmare (I rarely find books on this one)

Ask about any weird ships you ship as well because based on the fact I ship Reaper with Blue I don't think you will have a problem telling me a ship that I either just think is normal or can't think of right now