QUOTE(Comoop @ Mar 10 2019, 07:47)
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I don't understand what, "エチエチ", "キタ" and "wwww" stands for in this context ?
エチエチ - Incredibly lewd
キタ - Literally 来た, but used when excited/elated about something occurring or appearing
wwww - It's just laughing out loud. Sometimes you'll see typical seedy characters (e.g. otaku or just characters who are jerks) laughing at pretty much everything they say in hentai... This is all slangy stuff so I'd guess the character is meant to be sort of like a basement-dwelling loser type character who laughs at his own words a lot.
QUOTE(Comoop @ Mar 10 2019, 07:47)
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Also, later in the doujin in the intense sex scene when he fucks this girl, he keeps saying "ゼハ", what does it means ? Could it be something like: "take this"?
I don't think I've seen this before, but I would guess it's just panting. ゼー and ハー are just panting / hard breathing sounds by themselves so I'd guess it's just fast-paced hard breathing.