The title refers to a specific moment of conflict during this encounter. While Nanami provides instructions and specific boundaries—including the requirement for protection—the protagonist eventually penetrates and ejaculates inside her without permission. This act of "betrayal" or broken agreement is the source of the series' title, as Nanami confronts him with the line: "I told you to wear a rubber, didn't I?". Production and Reception
: Nanami is depicted with long black hair and a voluptuous design, serving as a primary figure in the "mature older sister" archetype common in this genre. Linguistic Context The title uses formal but stern Japanese: Gomu (ゴム) : Slang for a condom. Tsukete (つけて) : To put on or apply. gomu wo tsukete to iimashita yo ne...
必要なら、この一節を基にした短いブログ冒頭（日本語）か、続きの段落案を書きますか？ The title refers to a specific moment of