Resolved Some old-ish old manga/OVA

I don't remember much except for the fact that the girl MC was a robot and she died in the end leaving behind a sad tune that the male MC played with a guitar on the streets because he became a sad hobo. That's all I remember .-.
One of them had blue hair...I think? Although that doesn't help cuz 3/5 MCs have blue hair.

 

Saikano?

 

So how's the story goes by? Just romance or what?

 

I don't know how it ended, but I'm going to throw "Key the Metal Idol" out there.

Or maybe the video version of "Android Announcer Ana Maico"?

Although I can't think of either of them having a sad ending

 

Guilty Crown?

 

kowarekake no orgel
I believe this is the one you looking for.
I don't know how to put the image.

https://www.google.com.ph/search?q=...Rk-rcAhUMXSsKHa9FD3MQ_AUICigB&biw=320&bih=488

 

Chobits?

 

Aye, that's the one. Many thanks. I remembered the tune but couldn't remember where it came from XD