smegma
Often depicted as a cloudy or white substance built up under the foreskin of a penis. Significant buildup, colloquially "dick cheese", connotes a foul odor, color, and texture. Regular hygiene of the genitalia (not exclusively male) clears away much of the substance, which otherwise lubricates the affected tissues.

Pixiv
Twitter
Bluesky
Weibo
Lofter
Tumblr