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