Here is the full list of all 55 Yakuza Kiwami achievements. It takes around 80-100 hours to unlock all of the achievements on Windows.
Completed all substories.
Defeated Amon.
Upgraded all Majima Everywhere abilities.
Breaker Majima forced his way into a fight.
The Mad Dog of Shimano forced his way into a fight.
Spent a steamy moment with Rina.
Completed all training for Komaki Style.
Assaulted by Majima from a manhole.
Won against all rivals in MesuKing.
Completed the final chapter.
Completed "Man On a Ledge."
Assaulted by Majima from above.
Completed "Bet On A Champ."
Completed "Wife of a Yakuza."
Completed "The Fake Mizuki's Truth."
Obtained all Soul, Technique, and Body abilities.
Completed chapter 12.
Completed chapter 11.
Completed chapter 10.
Completed chapter 9.
Completed chapter 8.
Met the mysterious lady, Goromi.
Reached Rank B in Majima Everywhere.
Completed chapter 7.
Spent a steamy moment with Yui.
Completed "A Doctor's Duty."
Completed 50% of the Completion List.
Completed chapter 6.
Won all Pocket Circuit races.
Completed "My Baby's a Showgirl."
Completed 30 substories.
Completed chapter 5.
Met Zombie Majima.
Slugger Majima forced his way into a fight.
Completed chapter 4.
Successfully asked a hostess out on a date.
Completed 10 substories.
Thug Majima forced his way into a fight.
Completed "The Price of an F-Cup."
Got chased by Majima.
Met Officer Majima.
Completed chapter 3.
Completed chapter 2.
Obtained at least 10 Soul, Technique, and Body abilities.
Completed chapter 1.
Collected the money owed.
Obtain all other achievements.
Completed 100% of the Completion List.
Won all tournaments in the underground coliseum.
Enjoyed mahjong with a hostess.
Played all minigames.
Walked 1km during Premium Adventure while holding Haruka's hand.
Completed the game in Legend Mode.
Completed all of the Climax Battles.
Obtained EX Rank on Haruka's Requests.