This character is a Other Letter and is mainly used in the Katakana script.
The glyph is not a composition. 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+30ED offers a line break opportunity at its position, except in some numeric contexts. The glyph can be confused with one other glyph.
The Wikipedia has the following information about this codepoint:
ろ, in hiragana, or ロ in katakana, (romanised as ro) is one of the Japanese kana, each of which represents one mora. The hiragana is written in one stroke, katakana in three. Both represent [ɾo] and both originate from the Chinese character 呂. The Ainu language uses a small ㇿ to represent a final r sound after an o sound (オㇿ or). The combination of an R-column kana letter with handakuten ゜ – ろ゚ in hiragana and ロ゚ in katakana – was introduced to represent [lo] in the early 20th century.