This character is a Other Letter and is mainly used in the Katakana script.
The glyph is a canonical composition of the glyphs Glyph for U+30ADKatakana Letter Ki, Glyph for U+3099Combining Katakana-Hiragana Voiced Sound Mark. Its East Asian Width is wide. In bidirectional text it is written from left to right. When changing direction it is not mirrored. This katakana joins with other adjacent katakana to form a word. U+30AE offers a line break opportunity at its position, except in some numeric contexts.
The Wikipedia has the following information about this codepoint:
き, in hiragana, キ in katakana, is one of the Japanese kana, which each represent one mora. Both represent [ki] and are derived from a simplification of the 幾 kanji. The hiragana character き, like さ, is drawn with the lower line either connected or disconnected.
A dakuten may be added to the character; this transforms it into ぎ in hiragana, ギ in katakana, and gi in Hepburn romanization. The phonetic value also changes, to [ɡi] in initial, and varying between [ŋi] and [ɣi] in the middle of words.
A handakuten (゜) does not occur with ki in normal Japanese text, but it may be used by linguists to indicate a nasal pronunciation [ŋi].