This character is a Other Letter and is mainly used in the Hangul script. The character is also known as WAE.
The glyph is not a composition. It has no designated width in East Asian texts. In bidirectional text it is written from left to right. When changing direction it is not mirrored. U+116B forms a Korean syllable block with similar characters, which prevents a line break inside it. The glyph can be confused with one other glyph.
The Wikipedia has the following information about this codepoint:
ㅙ is one of the Korean hangul. The Unicode for ㅙ is U+3159. This compound vowel is ㅗ + ㅐ. To pronounce this vowel, shape your mouth to make the ㅗ sound. Then start to say the ㅗ sound and while quickly saying the ㅐ sound. The resulting sound is ㅙ (wae) as in ‘wedding’.