QUOTE(Quilloasa @ Jan 18 2018, 15:33)
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That's the sound of a penis sliding in all the way in one stroke.
FWIW I sort of disagree with this, though you definitely could be right. I based my interpretation off of [
www.weblio.jp]
https://www.weblio.jp/content/%E3%81%9A%E3%...%81%B7%E3%82%8A this entry, ultimately from daijirin.
(「と」を伴っても用いる)
Used with と, so a good candidate for being turned into SFX
①水や湯に全身ひたるさま。どっぷり。 「 -(と)湯につかる」
1. The state [a body] of
being fully immersed in water / hot water
②雨で全身ぬれるさま。ずっぽり。 「夕立で-(と)ぬれた」
2. Being soaked through by the rain.
③すっかり日の暮れるさま。とっぷり。
3. The state of the sun having completely set.
Which is why I went with *completely submerged* and flung a few insults at the nearest wall.
It's not really conducive to the english language either way though, so I don't have strong opinions on what to do with the sound - turning it into a generic schlk or something could work.