2, 4, 7, 26, B!

2) How easy is it for your character to laugh?
Very easy actually! Except in tlv. Or rather, it comes very naturally to him to chuckle at anything that amuses him and he finds a lot of people stupid or fascinating to the point of amusement.

(Aka: he's a lot less grumpy in canon where he's naturally at the top of the food chain in most scenarios and has a falsely cheerful attitude which comes with a lot of playful giggles.)

4) How easy is it to earn their trust?
Hard to impossible. Even people he works for or with do not actually hold his trust, he simply goes with the flow until the opportunity arises to change course to something more entertaining.

Likewise, he has no loyalty. He does not often work for anyone more than once. And he will literally turn on his current employer if the right opportunity arises.

7) What triggers nostalgia for them the most often?
Sounds, music. He likes to tell stories so possibly just questions asked and his own thoughts when they occur.

Do they enjoy that feeling?
Depends on the memory. He's quite fond of his contract kills. Earlier memories (say, from his childhood) not so much. He will, however, breeze over such emotions as if nothing bothers him.

26) What causes them to feel dread?
Not really a feeling he's used to/aware of feeling.

Perhaps in tlv where he's lived beyond his canon point, one could say certain types of eldritch entites and the sorts of things connected to them. An unconscious feeling to be certain though.

He hates magic and supernatural things, but that's not the same as feeling dread. He's killed witches and monsters so there's little fear there, only the thrill of survival.

B) What inspired you to play them?
I just really fell in love with him the moment he entered canon and couldn't get enough. I have a stupid soft spot for crazy Irishmen and stealth assassins. He's both. It was inevitable.

Also I love everything to do with music so his whole musical theme was a HUGE attraction for me.

I wish there was more of his singing... /sighs dreamily

HMM 10 and D! I was gonna ask 26 also but I see it's already been gotten to, haha

I'll do both this time!!

Collins:
10) What lie do they most frequently remember telling?
Collins lies by omission about his entire life. Mostly because he's a contract killer who refuses to be caught and punished for his crimes.

That said, however, he doesn't really have qualms telling his lifestory when it comes up. He doesn't lie about anything, just straight up answers. This also means you're probably about to die, oops.

Collins's active lies usually pertain to getting a job done and encompass a whole lot of range as he's known to pretend to be of another profession or even a particular person to get the job done.

He's adept at manipulating common folk and sweet-talking his way into places he wouldn't nornally be able to get to, or even getting out of trouble for something he did but nobody knows for certain.

He even entered a jail once and in secret killed a man and made it look like a suicide. This is pure canon. There's no telling what else he got up to over the years as well.

Does it haunt them?
No. His lies do not haunt him. He loves his job and he gets off on the thrill of doing a job well done.

Bonus:
In tlv I played off the (headcanon) idea that he lies to himself about his emotions and the fact that he can't feel them or that his emotions are "wrong" compared to normal people.

This is a direct result of his father being a complete jerkhole and, after an incident that upset said father, convinced Dennis that he came out wrong and that he couldn't feel emotions like love and caring for others.

Dennis doesn't actually have any issues with these emotions other than he misconstrues or misplaces them onto things that are generally frowned upon.

...bonus I say as if I haven't written way more than was asked for already.

D) What trait of theirs bothers you the most?
I'm gonna be honest and say I don't know or can't think of one. Other than the fact that he's a killer and in real life that would be a giant red flag.... I like what we see of him. I am totally charmed by him.

Does he have bad traits? Absolutely.

Can I think of any that annoy me enough to have an answer to this question? Not particularly?

If he didn't have them, his character wouldn't be as exciting.

Now if I was answering C as well there might be something that would seem like it fits here but. /shrugs

So maybe a rp vs rl is what makes the difference to this question. But yeah idk

Garrett:
10) What lie do they most frequently remember telling?
...he doesn't talk to people much so he has little cause to lie to others directly. Even then he's more likely to keep silent rather than tell a lie.

Hmm, but to himself...
He lies to himself about his need to have other people in his life. Or, as the old blind lady puts it, that he needs the city as much as it needed him during that time of crisis.

Because he can't actually steal anything if other people aren't there to steal from or for.

And more importantly even the most reclusive person needs a friend every now and again.

Does it haunt them?
Sometimes.
To be more precise, the incident with Erin haunts him. Related by the fact that he tried to have a person in his life, it went badly, and he's convinced himself that he's better off alone.

26) What causes them to feel dread?
Having to talk to people. LMAO. But not entirely inaccurate... he would rather face the Theif-Taker General in a duel than talk to someone (other than Basso).

More subtly and unconsciously, the City getting taken over by the supernatural sickness filled him with a deep seated dread he couldn't quite comprehend but knew it was there.

D) What trait of theirs bothers you the most?
Nothing. I love him.

RPing him, it's his desire to stay reclusive and lack of drive to interact with other people because it's hard to play when you're character just wants to fuck off and not do stuff with others. :c

I would love to live his hermit life but hooboy is it impossible.

Sometimes I try to bring in some of his past-self's traits to help compensate for this. He has those traits (the sarcasm, the witty verbage, dark humor, etc) but they tend to only come out when he's talking to himself in canon

because he doesn't really talk to anyone else in canon.

So I feel a little justified in extrapolating them for rp purposes. They exist within him as him and not just his past-self, we just don't get to see them used on others because of his reclusive behavior.

And done!