Here is the full list of all 55 The Assistant Season 1 achievements.
Reject Sarah on day 7 (Sarah's route 3)
Leave Beatriz's room on the night of day 5
Reject Iris on day 9
Don't be understanding with Beatriz on day 8
Invite Lisa on day 8
Don't enter the confessional on day 7 (Clarice's route 2)
Recriminate Christian on day 7
Ask Lisa on day 6 if she liked what she saw
Do it with Iris at her home
Do it with Iris at the disco
Help Sasha
Meet Sasha
Be understanding with Beatriz on day 8
Let Susan record on day 8
Listen to Harry's story on day 8
Go to Elaine's kitchen on day 8
Pretend to be asleep on day 7
Meet Mel
Meet Sophia
Enter the confessional on day 7 (Clarice's route 1)
Help Christian
Ask Christian if he's okay on day 7
Kiss Sarah on day 7
Meet Piper
Play along with Mrs. Bancroft on day 7
Check if Beatriz is Ok on day 6
Reject Zoe on day 6
Meet Zoe
Meet Eve
Be direct wiht Lisa on day 6
Accept Olivia's proposal
Meet Olivia
Accept Pamela's proposal unconditionally (Pamela's route 1)
Demand conditions from Pamela to accept the proposal (Pamela's route 2)
Reject Pamela's proposal (Pamela's route 3)
Check if Beatriz is Ok on the night of day 5
Meet Gwendolyn
Be kind with Roxy
Meet Roxy
Volunteer for Susan's experiment
Take a look at Susan's phone
Meet Beatriz
Meet Elaine and Clarice
Start Susan's route 2
Start Susan's route 1
Start Sarah's bad route
Start Sarah's good route
Help Sarah with Mrs. Bancroft
Meet Lisa
Take a peek at Sarah on day 2
Meet Grace
Meet Iris
Meet Susan
Meet Sarah
Meet Pamela