Here is the full list of all 32 Coming Out on Top achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Go with Ian to South America.
Take a laxative.
Commit the crime of rickrolling.
Sell a personal item that belongs to a famous pop star.
Cuckold someone for poor culinary skills.
Get your cavity searched.
Enjoy a cupcake.
Romance your pet fish.
Uproot a plant for a loved one.
Get Amos's romantic ending.
Get busy on a desk.
Taste one of life's finer pleasures.
Destroy a construction site.
Make it through the award winning film, "While I Sleep"
Try an exotic ice cream flavor.
Survive a kidnapping.
Jump up and down in a broken elevator.
Get Phil's romantic ending.
Win a game of trivia.
Get Ian's romantic ending.
Wear a top hat.
Get Jed's romantic ending.
Get Jed's sexual ending.
Get your mugshot taken.
Get Alex's romantic ending.
Drink milk like a boss.
Break the fourth wall.
Get Brad's romantic ending.
Graduate with honors.
Attempt to take down your university's corrupt athletics department.
Use Ian's toy.
Use Ian's lube.