Grima/Eowyn is a not-so-often explored pairing, which is a pity since there is so much potential in it.
If you dare, I'd like to see something that either shows some moment between them two that can be interpreted (or is) sensual/sexual - it does not have to be two-sided, but should not be non-con -
or some moment that shows a deeper understanding between both of them, especially in some unusual matter.
I'd prefer darker themes to fluffy ones - but in the end it's up to you! :)