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