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