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