Five Dates

Note: there are probably better options to unlock this, but these are all the dialogue choices I made to unlock the achievement.

Set your career as Other, and make sure your interests include Travel and Food.

Before the date begins when you are talking with Callum, make sure to choose to drink. This will also unlock the Hold my Beer achievement.

First Date
-No
-Sounds good to me
-Advanced
-Single for awhile
-Relationship
-Where are you going?
-Love the 1920s
-I understand

Second Date
-No
-Had a one night stand
-No
-Never
-Lied about my age
-No
-Agree
-Yes

Third Date
-With who?
-Are you talking to other guys?
-You matched my friend (Note: The Interrogation achievement unlocks here)
-Secure
-Yes

Achievement unlocks after the credits, which you can skip with RB.