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.
Don't kill anyone with Takuma during the mission “The Best Laid Plans.”
Kill Lady Chiyo without getting a disguise.
Kill or knock out 5 guards at the same time with all 5 characters.
Find all hidden caves in Hana Gakuen.
Execute a plan with all 5 characters.
Kill a samurai with a rock.
Kill Lady Chiyo with any character other than Aiko.
Kill 3 Samurai with Yuki.
Talk to a samurai when disguised with Aiko.
Finish “The Secrets of Hana Gakuen”.
Kill 10 guards with traps in Hana Gakuen.
Kill 30 guards with the help of the environment.
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.
Collect 17 badges.
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.
Travel 1200 meters in water during the mission “The Best Laid Plans”.
Kill a Samurai with a flower pot.
Find the perfect spot for sunbathing.
Hide 150 bodies.
Finish the mission “A Night at Sea”
Distract 4 guards at the same time with Kuma.
Kill at least 3 guards in the mission “A Night at Sea”.
Kill 10 guards with a drop attack.
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 a guard with a drop attack from a rope.
Throw a guard into a well.
Kill all enemies at the mansion in Nagoya.
Finish the mission “Reunion at Nagoya”.
Kill or knock out 150 guards.
Hide 50 bodies.
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.