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