Idols

Idols are humans born with power(s) and colourful hair, their hairs are usually bright and easy to see which is why some Idols dye their hairs (tough they have to do it every weeks as their true colour will magically come back). Idols, like other humans, have soulmates and more often than not their mates are other Idols.

BTS as Idols

Namjoon : metal/super strenght (can control metal, make metal, do things with it like bending it, can break/destroy pretty much everyrhing he touches, has a lot of difficulties controlling his strenght, etc.), metallic black hair, metallic blue eyes

Seokjin : earth/plants (can control/makes earths and plants, can heal people, can talk and listen trough plants he create, can understand animals living on land, etc.), forrest green hair, earthy brown eyes

Yoongi : ice/snow (can makes/control ice and snow, can freeze things/peoples, can makes snow fall, can makes ice/snow gollem, etc.), empath, snow white hair, icy blue eyes

Hoseok : water/poison (can control/makes water and poison, can breath under water, can understand animals living in water, any type of poison is useless against him, etc.), ocean blue hair, glowing purple eyes

Jimin : fire/lava (can control/makes fire and lava, can walk trough fire without being hurt, can swim in lava without being hurt, etc.), fiery red hair, molten orange eyes

Taehyung : wind/mist(can control/makes wind and mist, can float/fly in the air, can easily breath in places low on oxigen, etc.), silvery grey hair, misty indigo eyes

Jungkook : lightning/shadow (is a walking contradiction, can control/makes lightning and shadow, can transport himself and others things/peoples by walking in shadows, can do small and big shocks that can either ache or hurt a lot, etc.), yellow blonde hair, shadowy black eyes

Soulmates

Taehyung/Yoongi/Seokjin with Yoongi as the submissive (Seokjin and Taehyung aren't soulmates)

Jimin/Jungkook with Jungkook as the submissive

Namjoon/Hoseok with Namjoon as the submissive

Family

Seokjin, Namjoon and Taehyung are blood brothers

Jimin is an only child

Hoseok and Jungkook are blood brothers

All of them have soul bond with one another, soulmate bond and soul brother bond, the ones who aren't soulmates are soul brother, even the blood brothers, making them inseparable