Hikari sits next to 4 phonetic neighbors — Hikaru, Akari, and Kairi are the closest matches by sound. Most share Hikari's Japanese cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"full of fury, fierce, passionate"
"distinctive, of the family"
Similar sound: These names share phonetic patterns with Hikari — similar vowel sounds, consonant clusters, or rhythm.
Rhythm: Hikari is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.