Ochiru Iro wa, Kohakuiro
落ちる色は、琥珀色 · おちる いろ わ 、 こはくいろ
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
In a world still engulfed in war, Theo, who serves as a military lieutenant, feels uncomfortable around Kaguma, the captain of another unit, who constantly hits on him. However one day, while shielding Theo from a sniper, Kaguma sustains an arm injury that takes a month to heal. Feeling responsible, Theo offers to nurse Kaguma for the month until he recovers, but when he witnesses Kaguma masturbating, Theo ends up helping him deal with "that" as well...? (Source: Cosmic Publishing, translated) Note: Includes one extra chapter.
Source: AniList
External databases: AniList
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