Here is the full list of all 40 Leap of Faith achievements.
Stick to one girl all through the story
Lie at least three times during one playthrough
Comment on every nuke you can
Collect at least 30 images on your phone
End up with Linda
End up with Kira
End up with Robin
Sleep with 5 different girls in one playthrough.
Successfully sneak up on Steph
End up with Stephanie
Don't set Chris up with someone
End up with Holly
End up with Kira and Robin
Leave Steph behind
Flex at every opportunity
Well, that was unexpected
End up with Cece
Achieve a perfect score when helping Cece remember
Show great expertise as a rear end identifyer
Jump out the window at Steph's place
Play through the game once
See a minimum of 20,000 screens in Leap of Faith
End up with Lexi
Complete every task on your phone
Aquire 5 atletic trait points
Aquire 5 romantic trait points
Reach full speed at the bowling alley
Don't lie at all during a full playthrough
Try, but fail setting Chris up with someone
Have a threesome
Unlock every dialogue option when sunbathing with Holly
Aquire 5 flirty trait points
Find Robin's pin-code
Set Chris up with someone
Reach max points with at least 5 people in your contact list
Nuke something
Unlock the party on the plane
Find three easter eggs
Get a hold on Lexi's number on your own
Message Steph before you meet up with her again