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