Learn English – Usage of wide as a suffix

It is a question of grammar. You're looking for a word to qualify the way A and B are used, in the construct “to verb A and B qualifier”. This qualifier has to be an adverb (“a word or phrase that modifies or qualifies an adjective, verb, or other adverb or a word-group”).

Now, you want to express parallelism. “Parallel” itself is an adjective, as well as a noun and a verb. It is not an adverb, and as such, cannot be used in “using A and B parallel”. The natural adverb that derives from parallel is parallelly; though it's not exactly very common in general usage, it does exist and is attested in multiple (though not all) dictionaries. So, “using A and B parallelly” works.

Regarding in parallel, it so happens that it is a common phrase meaning “occurring at the same time and having some connection”. It may be more commonly used than parallelly, which is why it would feel very natural in your sentence, but both are correct.

When a female is described as pneumatic it means she has large breasts (possibly artificially augmented by plastic surgery).

To my mind, there's also the implication of her being both well-equipped and possibly available for bouncy bouncy / mattress dancing (slang euphemisms for sexual intercourse).

Per @z7sg's answer and @Jimi Oke's comment, Aldous Huxley particularly favoured the word, using it no less than 15 times in Brave New World! (less than half have any sexual connotation though - the majority are pneumatic chairs/sofas/shoes/etc.) Huxley's usage, which strikes me as somewhat bizarre, seems only loosely related to the standard meaning today.

The modern (sexist, to my ear) usage may have started with T.S. Eliot's Uncorseted, her friendly bust / Gives promise of pneumatic bliss (Whispers of Immortality, 1920). Over a hundred years earlier, and still sometimes today, the pneumatic body has been used to mean spiritual body which would be resurrected (as opposed to corporeal body which decays after death - see 1 Cor. 15:44).

I've never heard the term applied to a man, but if I did come across it, I wouldn't infer any sexual or spiritual conotations - I'd just assume it meant someone who looked a bit like the Michelin Man.