Boyfriend Dungeon

This is a list of known gifts that will be rejected by characters.

Ballet tickets — Pocket
Blue lipstick — Seven
Bouquet of daisies — Seven
Bracelets — Isaac
Chocolate truffles — Sunder
Concert tickets — Pocket
Fine bourbon — Rowan
Fine gold chain — Sawyer
Fried mackerel — Sunder
Gourmet cupcake — Sunder
Marskye cologne — Pocket
McQueen perfume — Sunder
Mystery novel — Sawyer
Opera tickets — Pocket, Sawyer, Sunder
Pepperoni pizza — Sunder
Raspberry liqueur — Sawyer (*might* reject it, but also might like it)
Single malt scotch — Rowan, Sawyer (*might* reject it, but also might like it)
Teddy bear — Valeria (this is the one I got the achievement with)
Travel guide — Seven, Rowan, Sunder
Vodka — Rowan, Sawyer, Valeria

The easiest to remember is to try and give Sunder basically any food item because he admits during the story that he’s on a strict diet and thusly rejects anything that goes against that.

I believe this achievement is missable although you'd really have to try hard to miss it. The reason being that you can only craft gifts once, and once you gift them (and not have them rejected) they're forever gone for that playthrough.

You can buy certain gifts like cinema and opera tickets but I don't believe they can be rejected by anyone, although I may be mistaken with this.

Just give an unhealthy snack like a cupcake to Sundar, Lipstick or eye makeup to Isaac or the Teddy bear to Valarian to pop this. If you're really stuck just take a good look at your available (non-purchased) gifts and give them who you think will reject them. If they don't reject then dashboard out straight away.