Hey Olivia, welcome. The coochie shave has now become a routine between my GF and I, so maybe I can offer something useful. Here are a few of the causes of irritation I can think of:

-- Inadequate prep. To prepare properly, you should:
- Wash the hair with soap to degrease it of waterproof skin oils, followed by:
- Hot shower or hot towel
- Apply shave oil
- Apply shaving soap & let it soak in for a minute while stropping or whatever

-- Inadequate lubrication.
- Use a shave oil (for coochie shaving, use a sex lube like System Jo)
- Don't let the lather get dry. Keep it wet.

-- Bearing down too hard on the blade.
This is easy to do, even if you don't think you're doing it. Shaving requires a VERY light touch. You want to get hair only. If you see dead skin accumulating on the cutting edge, you're pressing too hard.

I have yet to get my GF BBS because I've been concentrating more on safety, not so much on closeness. But she says that my barbering is the only irritation-free shave she's ever had.

Oh, btw, keep the soap (and, as you discovered, the alum) out of the opening. I also recommend using fragrance- and color-free soap. (Actually it was one of the ladies who first recommended that, I can't remember who). The classicshaving.com house brand has one. (The soap, not the lady).

Hope this helps,
-Johnny

PS: The kitty is funny