There is a woman named Ayane living in the apartment next to mine.
She's elusive and quite the tease, often taunting me with provocative expressions.

One day, I forget the key to my apartment work, and am locked out of my room.
She happens upon me, and ends up offering that I stay the night in her place.

From there on out, we become VERY close neighbors indeed...

(Source: DLsite)

Multi-work series list:

1. My Neighbor Ayane / Tonari no Ayane-san (となりのあやねさん)
2. My Neighbor Ayane Teasing Selfies and Smutty Punishment / Tonari no Ayane-san Itazura Jidori to Oshioki Ecchi Hen (となりのあやねさん いたずら自撮りとお仕置きえっち編)
3. My Neighbor Ayane Coincidental Meeting / Tonari no Ayane-san Desaki Battari Hen (となりのあやねさん 出先でばったり編)
4. My Neighbor Ayane Side Story THAT Room / Tonari no Ayane-san Bangai Rei no heya Hen (となりのあやねさん 番外・例の部屋編)

Note:
Live-action JAV adaptation: URE-101