Well the most obvious are of course Rin and Shiemi you can just see the manga/anime going towards that and such but well of course Yukio and Shiemi is one possibility too.We cannot also forget Izumo and Rin which might be possible but very unlikelyin a way but well see as the sotry progresses.I myself prefer Rin x Shiemi,Yukio x Shura,Shima x Izumo those just seem the most obvious ones in my eyes
I'm all rioting for Yukio/Shiemi. OTP since the very beginning. They fit each other very well. Yukio is someone mature and responsible who Shiemi could lean on, while her care and tenderness would sothe Yukio's worry and fatigue.
Rin and Shiemi... are cute. In completely platonic, non-serius way. Turning it into serious relationship would spoil the magic between them.
Shura/Yukio is a big NO. They know they can count on each other but hate each other guts. It's love/hate relationship without the love part.
I take guilty pleasure in Rin/Yukio : wateva brotherly love or incest I dig both.
Or Rin/Bon: pfff Rin did call Bon his princess XDDDDDDD