Here is the full list of all 44 Shadow Tactics: Blades of the Shogun - there are Aiko's Choice achievements.
Listen to everything Kuma has to say.
Finish all missions.
Kill Lady Chiyo without getting a disguise.
Kill a samurai with a rock.
Find all hidden caves in Hana Gakuen.
Kill Lady Chiyo with any character other than Aiko.
Kill or knock out 5 guards at the same time with all 5 characters.
Execute a plan with all 5 characters.
Finish “The Secrets of Hana Gakuen”.
Kill 10 guards with traps in Hana Gakuen.
Hide with all characters in a single bush.
Fail the Shrine riddle at the beginning 3 times.
Finish the mission “Red Lights at Matsuyama”.
Don't extinguish any light sources in Matsuyama.
Don't kill anyone with Takuma during the mission “The Best Laid Plans.”
Collect 17 badges.
Kill 30 guards with the help of the environment.
Hide 150 bodies.
Find the perfect spot for sunbathing.
Finish the mission “The Best Laid Plans”.
Kill the Captain.
Kill 10 guards with Takuma's Sniper Rifle that are farther than 25 meters away from him.
Kill 3 Samurai with Yuki.
Travel 1200 meters in water during the mission “The Best Laid Plans”.
Kill at least 3 guards in the mission “A Night at Sea”.
Finish the mission “A Night at Sea”
Distract 4 guards at the same time with Kuma.
Kill a guard with a drop attack from a rope.
Kill a Samurai with a flower pot.
Talk to a samurai when disguised with Aiko.
Kill all enemies at the mansion in Nagoya.
Use Aiko's disguise 15 times.
Come out of the other side of the river in Nagoya.
Hide 100 bodies.
Distract 50 guards with Hayato's stone.
Kill 10 guards with a drop attack.
Kill or knock out 150 guards.
Hide 50 bodies.
Finish the mission “Reunion at Nagoya”.
Kill or knock out 100 guards.
Kill 20 guards with Mugen's Swordwind.
Kill or knock out 50 guards.
3 times in one mission, kill 2 guards at once with Mugen's Swordwind.
Throw a guard into a well.