伴う
ともなう · tomonau · JLPT N1 · verb-godan
to accompany
👫 ともなう sounds like tomo (friend) + nau: a friend who comes along with you
伴 = person radical 亻 + 半 (half): a companion is the other half who walks beside you. Use it for things that come along with other things, like 責任を伴う (to bring responsibility with it).
伴 — person radical 亻 + half 半
A semantic-phonetic compound: 亻(person) gives the meaning and 半 (bàn, 'half') supplies the sound while also hinting at 'one of a pair.' The original sense was 'companion' or 'partner,' someone who is your other half, and from there it extended to 'accompany.'