Mai + Shizuka
Nurseshipping is among the top popular pairings for yuri (I believe that they are Nurseshipping, Sideshipping, Danceshipping, Visionshipping and Anzu/BMG; Mai/Shizuka, Anzu/Shizuka, Mai/Anzu, Mai/Isis, repsectively). It’s probably tying with Sideshipping for “most fluffy and sweet” because many fics focus on Shizuka looking up to the older girl. Usually it’s Mai falling for Shizuka’s innocence or Shizuka for Mai’s older “experienced woman” aura.
You are most likely to find fanfics that are WAFFY or slightly angsty, in which one girl worries over not being able to be with the other (Sadly). There are very little fics that are very sexual in nature, and it is very rare for Shizuka to be “topping” Mai.
The Talk by Regann – The fact that the pairing is MaiShizuka is supposed to be the twist, so reading it twice is a good thing to do. Though Shizuka doesn’t really show up in the fic much, it’s an interesting perspective on the dynamics of how Joey would react to the relationship. (Complete)