I'd imagine that hair care in the 24th century would be quite a bit better than just a hot iron.

After all, they can regrow skin with a little wavy light thing,

Then again, Gene Roddenberry was once asked about Picard's baldness. The interviewer asked if people would have a cure for baldness in the 24th century, Roddenberry said that they wouldn't care about the baldness in the 24th century.

The transporter can flip that switch. "Worf to O'Brian. Beam with me to 10 forward with a bob."

Oh I thought it was because he was just braiding it at night, never imagined there were Klingon curlers

Worf had a secret career as a beauty vlogger.

Klingon pain sticks double as curling irons

Either that or he crimps it.

That's not all worf's hair. Some of it was acquired in battle.

https://memory-alpha.fandom.com/wiki/Mot

Thee was a barber on Enterprise-D.

Worf being asked out on a date by someone he would rather not:

“I can’t that night. I’m doing my hair.”

That's great. He looks like he has hair like me, which is quite curly IF you take care of it: wash and condition 1-2 times a week. It gets ratty if you don't and the curls start to fall out and they frizz (individual hairs curl separately).

And you can definitely straighten your hair with heat, which holds till a wash.

The old pic below also checks out: grey and white hairs are a different texture and mine are significiantly less curly than the rest of my hair. So it makes sense old Worf's hair is straighter.

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It's disrespectful to the gut you're stabbing to be unkempt.

Okay but that drawing looks like it came straight from filmcow.

https://youtu.be/LdVuSvZOqXM?si=jWfr6tonO8dtfGtX&t=30