I'm not sure of specific Yukina x Kisa non - mpreg fanfics. But you can try searching on popular fanfic platforms like Archive of Our Own. Use the tags 'Yukina' and 'Kisa' and exclude any mpreg - related tags. You might find some great stories about their relationship in other themes like friendship or adventure.
Finding specific non - mpreg fanfics for Yukina x Kisa can be a bit of a search. You could start by looking at general anime or manga fanfic directories. Some fanfic authors might focus on the more platonic or romantic (non - mpreg) aspects of their relationship. Try to read the summaries carefully to ensure it's not mpreg - related. Also, you can look for works by authors who are known for writing non - mpreg content in general and see if they have any for this pairing.