Tsuki Namiko♀

Tsuki Namiko is an English teacher at Kashima high school, and is the homeroom teacher of Hazumu's class. As she often proclaims, she has lived for thirty-five years and has never had a single boyfriend. This has enabled her to devote most of her time and energy into her students at school, but she is still lonely. When Hitoshi starts to work as her coworker at school, she becomes instantly infatuated by him, and goes to extreme lengths to show her devotion and mania towards her precious Hitoshi Sora. Namiko's attraction towards Hitoshi borders on obsession as she hangs large pictures of him on her walls at her home, and constantly is thinking or dreaming about him. However, since Hitoshi's species cannot express emotions, the attraction is entirely one-sided.

[From Wikipedia.]