Trying to remember everything correctly it was a comedy fantasy (IIRC) where the FL is like a princess, I don't think she's very smart but once she gets into a fight she gets very blood thirsty and becomes a berserking sadist.

One of her companions is like her teacher or the party's healert but he's the ML. The ML is a masochist who purposefully got in her way so that he's stabbed, cut, bloodied but no problem because he's immortal.

That's all that I can remember. I know it's not masochist tank and the sadistic healer. But I recall reading them close together. Please help if you can

Nevermind I found it myself after a bit of rest.

"Cursed Princess And Her Immortal Servant"