noun
erect nipples visible through clothing
Slang term referring to the outline or protrusion of erect nipples seen through a shirt or other clothing. Often used in casual or online contexts.
薄いTシャツだと胸ポチが目立つから気をつけて。
Be careful with thin T-shirts because your erect nipples might show through.
彼女の胸ポチに気づいて、ちょっと恥ずかしくなった。
I noticed her nipples were visible through her clothes and felt a bit embarrassed.