Hmm, I was just talking about this in the SRB2 chatroom the other day. So this time I'm actually prepared.
Do not want to meet:
- Alice: As much as I like her character, there's no doubting that she'd probably make things very uncomfortable for you if you tried to hold a conversation with her.
- Youmu: Speaking of emotional detachment, I don't think Youmu would have any patience to talk to me. Her mistress is also a tad temperamental, and as cool as it'd be to see the queen of the netherworld, one might question the wisdom of dropping by for a chat.
- Remilia & Sakuya: I wouldn't be too keen on visiting the vampire they call the "Scarlet Devil". Nor would I want to see Sakuya, who is emotionally detached when it comes to humans.
- Yukari: If you don't find the concept of running into a mischievous omnipotent youkai deeply disturbing, then you clearly don't value your sanity... or life
- Tenshi: I don't care for meeting brats that have nothing but their appearance. Meeting a celestial with that personality would be dangerous and very frustrating.
Miiiight not regret:
- Ran: She seems a caring sort, but I wonder if I could bring myself to trust a kitsune.
- Reimu: I expect I'd end up meeting her sooner or later. Preferably it'd be during some kind of tour in which she desperately tries to get donations, rather than being accused of putting hats on the statues.
- Reisen: First off, I'd need to get some headache medicine from Eirin to make eye contact. Now while Reisen is probably responsible and polite enough to keep it from turning into a sour encounter, she's probably also responsible and polite enough for it to be mostly an awkward silence. I used to identify with that though, but lately I've been slacking off in both departments.
- The Yama: No, it wouldn't be a pleasant experience. One would expect her to be a little preachy (although I personally found ZUN's endings more preachy than her dialogue) and confrontational. That said, I wouldn't discount the value of being able to confront your greatest sin in some sort of trial (as in test, not as in court :V).
Want to meet:
- Kaguya: "Tale of the Bamboo Cutter" is my favorite folk tale, and since the Lunatic Princess is so obliging with stories, I'm sure it'd be an educating experience.
- Marisa: I'm sure everyone here has that one friend who you have an excellent time with, but would probably hate if you had to spend too much time with. I'm certain Marisa would be one such acquaintance.
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I've also heard that the Moriya trio would probably have the most normal conversation with you (me, I can't picture having a normal conversation with a god... I can barely talk to priests!) and I've also been told that I would probably get along well with Komachi. I'm not going to include the characters you'd only meet because they'd waylay you in the middle of your journey.... that is, most stage 1&2 bosses. Nor am I going to include characters that would be a blatantly horrible idea to meet, like Flandre, Yuka, or Medicine.