Simple Yet Sexy

The usually quiet girl is moving her hips on her own... Asking me to go deeper... Letting me do whatever I want... This side of her only I know... I want to see more of it.

(Source: Coolmic)

Volume 1: Jimihen!!: Jimiko wo Kaechau Jun Isei Kouyuu (じみへんっ！！～地味子を変えちゃう純異性交遊～)
Volume 2: Jimihen!!: Jimiko ga Torokeru Dekiai Seikou (じみへんっ！！～地味子がトロける溺愛性交～)
Volume 3: Jimihen!!: Jimiko mo Midareru Zecchou Seikou (じみへんっ！！～地味子も乱れる絶頂性交～)
Volume 4: Jimihen!!: Jimiko ni Himitsu no Haitoku Onsen (じみへんっ！！～地味子に秘密の背徳温泉～)

Notes:
- Includes 4 extra chapters.
- Originally serialized as a web manga under the title Jimiko wa Igai ni Erokatta (地味子は意外にエロかった).
- Released in long-strip format and subsequently sold in traditional format.