Shiki's bespectcled Senpai.

An upperlcassman at Shiki's school who runs and makes up the entirity of the Tea Ceremony Club.

A reliable and serious student who all in the school know they can fall back on for help if they need to, and a sometime member of Shiki's friendgroup despite being in the year above.

A completely normal student at a completely normal school.

There is nothing strange here, everything surrounding Ciel-Senpai is fine.

Even if Shiki can't exactly place when he met her.