Spoiler Warning!
It's a bakudeku story placed in a future setting (where deku is the number 1 hero). It begins with bakugou getting a call that deku has died, which made bakugou the number 1 hero. Throughout the story, bakugou pretends deku is still at home with him and thinks back at their old memories. Later on, bakugou learns that while deku was dying during his mission, deku was holding onto his phone, and wanted to send his final text to bakugou, which was "I love you". In the end, bakugou also dies during a mission, and gets reunited with deku, where he got to actually hear deku say "I love you" and learns that deku was watching over him all this time.
seriously my heart needs to recuperate now