Napstablook- or Blooky, as Frisk had started calling them- was shy, quiet, self-conscious and anxious. They were also sweet and nice, and had been rather taken with Frisk from when they had first met in the ruins. Frisk's patience and kindness was just what the little ghost needed; and although they were busy with school and art and their closest friends, they tried to make time for the ghost.
The door to their little house, as ever, was unlocked, and Frisk headed straight in. Napstablook had their headphones on, but they heard the door and greeted Frisk... about as enthusiastically as they were able to.
"Oh... you came... I didn't know if you would, you have so many friends."
"So many other friends," Frisk reminded them.
"Oh... yes, of course... Well... I found some more music to share with you."

Napstablook loved to share the music they liked, and although Frisk hadn't really had much prior knowledge of music, it had helped them form a bond. The human had responded by sharing video game music they liked, and they'd explored other genres and bands together. The little ghost seemed to revel in it, to be able to do something for someone they admired so much.
They quickly pulled up a series of music videos and tracks. "What do you think to this one..."

It was more... energetic than most music Frisk had heard before. Powerful energy, that reminded them of Undyne, full of passion. The instruments were loud, guitars singing over drums and the vocals raw and powerful. Usually they gave their opinion of a track pretty early in, but they listened to this all the way through, not wanting to speak over it.
"That's amazing, Blooky!" they said, once it was over. "Wow... I've never heard anything like that. It was like... Fire and passion and-" they laughed, "-and determination."
"I'm glad you liked it... it's not what I usually listen to but I thought it might be right for you, because you don't ever give up."
"That's... Thank you." Frisk gave him a genuine smile; he almost returned it.
"I found more... if you like..."

The intro to the next one was heavier and Frisk sat forwards, listening intently; but as soon as the vocals kicked in, they made a face. "Eurgh, no, it's all... Growly! I don't like that at all."
"Oh no... okay... so no vocals like that... I'll see what I can do..."
"Hey, I found something I wanted to share with you, actually!" They pulled out their phone, where they'd saved the link. Napstablook copied it into their computer and let it play while they went through the playlist they'd put together for their human friend, removing certain songs.
The one Frisk had picked out was an orchestral piece; slow and sweet, but with a slightly haunting tone to it. It had given Frisk goosebumps the first time they had heard it; and it did again now, listening together at the slow strings and whispering woodwinds. The ghost turned to them as soon as it finished.
"That was really nice... thank you..."
"It made me think of you!"
"Oh... oh no..." Napstablook's eyes swam. "Oh... Why?"
"Because... It was gentle, and nice, and- um." Napstabook was crying now- although that was quite normal for the little ghost. Frisk didn't know what to say when he did it though, so they just gave him a gentle smile.
"Oh... Thank you... that was so nice... Oh... I'm rambling... I'll put the next song on for you..."

Frisk stayed a while, listening to songs and giving them their opinions on them. Napstablook had sorted out a playlist; although they'd gone with an older phone, they could listen to some music on it, although it couldn't hold much. The ghost would regularly update their phone with music they'd found, and Frisk would listen to it while drawing; they could have changed up their playlist at home, but this was an excuse to come and see Napstablook. The style of music they listened to would alter what they were inspired to draw or paint, and having music that connected them to their friends was the best part of all, to them.

Really short one... I wanted to show Frisk spending time with Napstablook, cherishing that ghost! But writing people just hanging out and listening to music together is tough- doubly so when you don't want to name names (as I didn't.)
But it seems Frisk likes rock and roll and metal music, as long as it's not too heavy. I can see them enjoying the energy in it, and it being a good stress release and inspiring their art.

Don't worry, the next ones won't be this short!

-Ren