Fics like The Heaviness of a Heart

Karamatsu joins a forum for suicidal people. He lacks the courage to kill himself on his own, but finds someone that has the same problem living in the same city. The two make a pact to kill themselves together, but upon their meeting Karamatsu finds that it was his brother Choromatsu. Now Karamatsu has a new mission, to stop his little brother from killing himself. A fanfic about two sad boys just trying their best to survive.

You may also like

clumsy. by FiveTail (おそ松さん | Osomatsu-san (Anime))
Time and Time Again by suudonym (おそ松さん | Osomatsu-san (Anime))
Open Skies by xxiiyu (おそ松さん | Osomatsu-san (Anime))
Arduous Equanimity by Kawamatsu-san (おそ松さん | Osomatsu-san (Anime))
The New Super Ridonculous Race by Thenewsubwayguy (Family Guy (Cartoon), American Dad!, more)
Now or Never by ikamatsu, orphan_account (おそ松さん | Osomatsu-san (Anime))
Requiem for a Regrettable Romance by pregnantzombie (おそ松さん | Osomatsu-san (Anime))
Was it Fate? Roommates from Hell by orphan_account (おそ松さん | Osomatsu-san (Anime))
The Many Moods Of Matsu Makeouts by ToiletPaperPrincess (おそ松さん | Osomatsu-san (Anime))
A Double Charade by zelkova (おそ松さん | Osomatsu-san (Anime))
Something Worth Salvaging by grimrester (おそ松さん | Osomatsu-san (Anime))
Osomatsu Hates Feelings by dagger (おそ松さん | Osomatsu-san (Anime))
Always There by orphan_account (おそ松さん | Osomatsu-san (Anime))
Four Guys by Philiah (モブサイコ100 | Mob Psycho 100, Gravity Falls, more)
smother me by rire (おそ松さん | Osomatsu-san (Anime))
The Fox and His Turkey's by Betsubara (おそ松さん | Osomatsu-san (Anime))
Fappymatsu is a Host!? (おそ松さん | Osomatsu-san (Anime), Ouran High School Host Club - All Media Types)
I'm Not Saying I'm a Mess by DaisyC (おそ松さん | Osomatsu-san (Anime))
Wrong by PineappleRain (おそ松さん | Osomatsu-san (Anime))
Ś̶̻I̵͑͒̇͜͝C̵͎̮̹͈̟̊Ķ̶̧̻̘̊̀̚ͅ,̸̼̘̭̎̔̓ ̵̬̋̔̎̊̚͜S̸̡͑̈́͑Ï̷̢̖̗͓̔̓C̶̞͈͗͌͘K̵̳̹̦̪̈͂,̵̪̈́̂̏ ̸̜̦͔̏̾͑͜S̴͎̣͜͠I̷̱̓C̶͖̝̳̮͈̆̂̆̾̕Ḱ̵̢̻̘̲͙͑̆͊ by Lexsssu (Your Boyfriend (Visual Novel), Our Life: Beginnings & Always (Visual Novel), more)