Yanagisawa is one of the easiest opponents in the game, as you can beat him with sweeps. Just keep crouched and use the strong kick over and over, you can keep tripping him up until he's defeated. This is the best and easiest strategy to use, as if you keep doing this he tends to only use his own crouching kicks and punches. If you try anything else, he tends to use his counter to stop you, which does a decent amount of damage.
Another strategy is to jump in with a strong kick, then do a standing strong kick, then do a crouching strong kick. This is riskier because Yanagisawa is prone to using his own rapid punches. Generally speaking you want to stick with the sweeps to win.
This fight against Kandori is much easier than the last encounter with her. Natsuki can now use the energy bomber move, which is a good move to use against Kandori -she frequently tends to walk straight into it. She will still use her counters, but it's not as bad as before.
Natsuki can also use the double energy bomber move now as well, but you can only do this when the stun gauge is red. Kandori has a habit of using one of her dash moves if you try a jumping attack at her, so keep using the energy bomber as it's the best move for this fight.
Bigaro is a big guy, but he can use his dash moves to move around quickly. He tends to use his lift up throw a lot, but his rolling attack is the one to watch out for -this can take a lot of health off even when blocked.
The general plan with Bigaro is to get to either side of the screen, block whatever attack he uses, then counter with either the weak or strong kicks. It'll take a while to wear him down, but it's the easiest way to beat him.
Tsuguo has a projectile attack -it won't travel the full length of the screen, but he will use it to knock you back if you get in its range. His main strategy is to use his encircling fist technique. He can only use this if his stun gauge is in the red, but it's his best move. If you get hit by this at close range, it'll deplete your stun gauge even if it's full! He also has a dragon punch style move which not only hits on the way up, but also on the way down. He doesn't tend to use it even if you jump at him though.
He also has a decent counter move, which will knock you well back if he hits you with it. One strategy is to get his stun gauge red, then quickly move back. When he uses his encircling fist, try the energy bomber and time it so it hits him as he spins towards you.
Kandori is a lot smarter this time around, as she'll now counter the energy bomber if you try and do it near her. She has all of her other moves from before, along with a new one: the thunder mountain storm. This is a variant of her mountain storm throw, but like her other command grabs, it can be blocked. Do not use the smash and rend move against her, she'll almost always counter it, and her counter can take a lot of life from you. The best strategy against Kandori is to jump in with a strong kick, then do a crouching strong kick.
Another fairly consistent strategy is to jump in with a strong punch or kick, then uses the concentrated punch move as soon as you land. This is especially effective if you have Kandori in the corner, as whilst she'll usually block the jumping attack, she'll end up getting hit by the concentrated punch.
What happens next in the story now depends on the following factor: did you use a continue?