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. The word that U+025B forms with similar adjacent characters prevents a line break inside it. The glyph can be confused with one other glyph.
The Wikipedia has the following information about this codepoint:
Latin epsilon or open E (majuscule: Ɛ, minuscule: ɛ) is a letter of the extended Latin alphabet, based on the lowercase of the Greek letter epsilon (ε). It occurs in the orthographies of many Niger–Congo and Nilo-Saharan languages, such as Ewe, Akan, Lingala, Dinka and Maasai, for the vowel [ɛ] or [e̙], and is included in the African reference alphabet.
In the Berber Latin alphabet currently used in Algerian Berber school books, and before that proposed by the French institute INALCO, it represents a voiced pharyngeal fricative [ʕ]. Some authors use ƹayin ⟨ƹ⟩ instead; both letters are similar in shape with the Arabic ʿayn ⟨ع⟩.
The International Phonetic Alphabet (IPA) uses various forms of the Latin epsilon:
U+025BɛLATIN SMALL LETTER OPEN E represents the open-mid front unrounded vowel
U+025DɝLATIN SMALL LETTER REVERSED OPEN E WITH HOOK represents the rhotacized open-mid central vowel
U+025EɞLATIN SMALL LETTER CLOSED REVERSED OPEN E represents the open-mid central rounded vowel (shown as U+029AʚLATIN SMALL LETTER CLOSED OPEN E on the 1993 IPA chart)
The Uralic Phonetic Alphabet uses various forms of the Latin epsilon: