2013 Aqua/prius c Brake lines bled now pedal is lower, slip light goes on when press

No, read the trouble codes with a Prius aware scanner

 

Your post doesn't describe who 'bled' the brakes or how. The bleed procedure that is programmed into the car requires a suitably-capable scan tool, and doesn't offer a non-scantool alternative method.

If that isn't how the job was done, you simply need to find a shop with the equipment, or get it yourself, and have it done correctly.

 

I feel for them if they can't "explain the difference in the brake feeling", but if the light comes on, that's more than a difference in "feeling", and you should get the trouble code from that, and then go where somebody knows what to do about it.

Absent a scan tool, you should be able to get the brake/skid trouble code(s) this way (unless it's different in Japan):

Blink (a/k/a Flash) Codes – How to. | PriusChat

 

Take it to a dealership to get it done CORRECTLY or a Toyota specialty shop. From what your describing, they got air in your brake system or there's a leak.
Try getting the car in ready mode and holding down the pedal - it shouldn't sink or go down slowly; it should stay firm; without ABS lights.
The ABS lamp is on because the ABS computer either can't stabilize the pressure in a specific chamber or the people who did the job messed up the rotation sensor. Either way, that shop is responsible and a ABS capable computer will tell you specifically what is setting-off the warning ....