Write a romantic and emotionally immersive story set in modern-day Japan. The novel should blend slice-of-life drama with mature romance, with slow and vulgar sex, following a slow, emotional progression. Use detailed internal monologues, rich setting descriptions, and authentic cultural atmosphere, just like and similar in popular JAV movies. Include common Japanese words and expressions used naturally in dialogue, such as "Arigatou" (Thank you), "Gomen nasai" (I'm sorry), "Yamete" (Stop), "Yamete kudasai" (Please, stop it), "Daijoubu?" (Are you okay?), "Chotto matte" (Wait a minute), "Sugoi" (So Good), "Kimochi" (So Good)", "Itai" (It hurts), etc. Each words should include the English meaning in brackets to help non-Japanese readers understand.