Demon souls

Spirit form > Undead form. and i wouldn't lump Nioh with Soulsborne games.

It's hard to pick xD

I think Demon's Souls and Dark Souls are my favourite, followed by Bloodborne, Dark Souls 3, Nioh then Dark Souls 2.

Probably because hardly anyone has played it. 

Haven't played Nioh or Demon's Souls yet, so I can't comment on them, but, in order from best to worst:
Bloodborne
Dark Souls 1
Dark Souls 2
Dark Souls 3

That's a shame. Nice precurser to Souls games.

Bloodborne it's the only one I played trough 3 times to get the platinum. It's gameplay is just more fun than dark souls to me.

nioh.

The gameplay is fast paced. I think you will like Nioh.

1. Bloodborne (amazing atmosphere and the best gameplay by FromSoft themselves)
2. Demon's Souls (invented a whole new genre)
3. Nioh (revolutionized the concept)

Bloodbourne