Here’s the South Carolina state law.
SECTION 16-15-130.Indecent exposure; breastfeeding.
(A)(1) It is unlawful for a person to wilfully, maliciously, and indecently expose his person in a public place, on property of others, or to the view of any person on a street or highway.
(2) This subsection does not apply to a woman who breastfeeds her own child in a public place, on property of others, to the view of any person on a street or highway, or any other place where a woman and her child are authorized to be.
(B) A person who violates the provisions of subsection (A)(1) is guilty of a misdemeanor and, upon conviction, must be fined in the discretion of the court or imprisoned not more than three years, or both.
HISTORY: 1962 Code Section 16-413; 1952 Code Section 16-413; 1942 Code Section 1442; 1932 Code Section 1442; Cr. C. '22 Section 383; Cr. C. '12 Section 390; 1906 (25) 84; 1965 (54) 577; 1993 Act No. 184, Section 180; 2006 Act No. 269, Section 2, eff May 2, 2006.
Myrtle Beach prohibit thongs and Horry County, in which it’s located, prohibits exposure of the buttocks.
Sec. 5-30. - Nudity, display of specified anatomical areas and specified sexual activities prohibited.
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(d) G-strings, T-Backs, “dental floss” style, and thongs are prohibited in public. Body paint, body dyes, tattoos, and liquid latex or similar materials are not considered adequate coverage pertaining to the specified anatomical areas.
Sec. 5-21. - Public nudity prohibited.
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(b) It shall be unlawful for any person to intentionally appear on any public beach, beach access, in the public waters, any other public property, or in view of the public in such a state of dress or undress so as to expose to the view of others the human male or female genitals, pubic area, pubic hair, buttocks, anus, vulva, or any portion of the female breast at or below the areola thereof.
I haven’t done extensive search, but not all counties in South Carolina seem to have the same restrictions. For example, the Charleston County Code of Ordinances don’t appear to include anything about exposure, and here’s the Charleston law.
Sec. 21-166. - Indecent exposure.
No person shall appear in any public place or on property open to the public in a state of nudity or otherwise make any indecent exposure of his or her person.
(Code 1975, § 37-56; Ord. No. 1982-4, § 1, 1-12-82)
State Law reference— Indecent exposure, S.C. Code 1976, § 16-15-130.
Isle of Palms, which is also in Charleston County, is more restrictive.
Sec. 9-4-2. - Indecent exposure.
It shall be unlawful for any person to appear in any place in the City open to the public in a state of sexually explicit nudity. The term “sexually explicit nudity” means the showing of uncovered, or less than opaquely covered, human genitals, pubic area, or buttocks, or the nipple or any portion of the areola of the human female breast; or covered human male genitals in a discernibly turgid state.
(Code 1994, § 9-4-2; Ord. No. 1994-4, § 54, 4-26-1994)
State Law reference— Indecent exposure, S.C. Code 1976, § 16-15-130.