The only son of [Yumiko](https://anilist.co/character/308785)'s neighbors, the Yamamoto's. He's always looking for a good time and hitting on sluts and women at clubs with a high rate of success (though his success rate on the streets is low).

Yumiko's husband always goes on business trips during the Obon and year-end holidays. When Yumiko was feeling lonely and having a hard time with her sexual desire, she found a hentai doujinshi in her husband's room during his business trip. Her husband, who she thought didn't have a strong sex drive, has this book... While Yumiko is masturbating and imagining intense sex with her husband like in the doujinshi, a young man who lives in the neighborhood comes up to her and...? Unable to resist the young man's intense sex, Yumiko is drowned in her own lust...! 
 
(Source: Lune-soft, translated)

Protip if you have a significant other: make sure you have enough sex so neither of you is left sexually frustrated. Our heroine Yumiko was left in that state by her husband when he went on a business trip (actually, he went to Comiket), so when a young, horny stud of neighbor came over, she found it very hard to resist his advance~ 
(Source: Fakku!) 
 
1. chapter 1 (第1章); Comic Market 94 
2. chapter 1.5 (第1.5章); COMIC1☆15 
3. chapter 2 (第2章); Comic Market 96 
4. chapter 3 (第3章); Comic Market 98 
 
Notes: 
- The author wanted to put the story of chapter 1.5 into chapter 1, but didn't get to so he published it later in the spring as an extra. 
- A live-action AV adaptation (URE-074) was released on November 9th, 2021.

1. Tsuma ni Damatte Sokubaikai ni Ikun ja Nakatta 1 (妻に黙って即売会に行くんじゃなかった1); Comic Market 94, COMIC1☆15 
2. Tsuma ni Damatte Sokubaikai ni Ikun ja Nakatta 2 (妻に黙って即売会に行くんじゃなかった2); Comic Market 96 
3. Tsuma ni Damatte Sokubaikai ni Ikun ja Nakatta 2.5 (妻に黙って即売会に行くんじゃなかった2.5); kakioroshi 
4. Tsuma ni Damatte Sokubaikai ni Ikun ja Nakatta 3 (妻に黙って即売会に行くんじゃなかった3); Comic Market 98 
5. Tsuma ni Damatte Sokubaikai ni Ikun ja Nakatta Epilogue (妻に黙って即売会に行くんじゃなかった エピローグ); kakioroshi 
6. Batsuichi Komochi Zenpen (バツイチ子モチ 前編); Comic Market 100 
7. Batsuichi Komochi Kouhen (バツイチ子モチ 後編); Comic Market 101

Kazuya Yamamoto