Get haunted by a ghost.
Poltergeists, whilst common are pretty ineffectual for public transport. You’d have to bring your own plates to smash.
Ancestor spirits sadly depend on the family. My ancestor spirits stopped talking to me when they discovered I like anime. I have a buddy who has a hussar spirit ancestor and he even has a horse.
Wraiths are pretty great. They usually come with their own chains and have the uncanny sense of detecting LSD. They do sort of disappear in sunlight but I think that’s not a problem on the subway.
Spectres are your good all rounder. They’re the most human, can keep up to date with modern culture so you can even tell them about CWC.
Then there are the more exotic types;
Onryo, my personal weeaboo choice, though taking care of one is hard. They tend to be quite aggressive to those similar to their target for “revenge”, and need at least a basic knowledge of Japanese conversation. Be careful with deals on them though, getting them from an Onryo mill is unethical.
Djinn are an odd case because oftentimes we just get the same ones coming back each time. Saying their true name does NOT give you power over them, it in fact curses you and I feel it was some dumb Discord gayop that spread it around to endanger people. They do however all have a very upper class personality so if you do get one they tend to be very interesting.
Mummies are physical undead so you need to walk them often. Despite stereotypes they’re actually very clean, they just decayed enough that need to bathe in mud to sweat. They do tend to be package deals though, as unless it’s a stray most Mummies have an entourage ranging from their servants and pets all the way to entire dynasties.
Lastly there’s demons. Don’t even bother, there’s a reason Demons are banned from the parks. Also be careful going to shelters as half the species there tend to be a Demon or Demon mix but given the name of a different breed. And so often the Demonmommies will be wondering why their precious little thing has attacked and eaten their child.