Bruh, you haven't even seen the third boss yet. It's literally unfair. The horns are too tall to dodge effectively, there's shit flying everywhere to a quite psychotic degree, the platforms are too damn small, he has a huge pool of hitpoints, he has way too short of a vulnerability window to do any more than damage equal to 3/10ths of his hitpoints, if you're lucky and get the full three jumps worth of thrusts and dog spirits. Not to mention a particular enemy before hand that will invariably remove one hitpoint off of you before you even get there (The other is laughably easy if you have good reflexes and timing). And all of this is WITH the Bikini, Magic Shield, Magic Sword, Water Jug, etc. This is like taking the Sans battle from Undertale and making it far harder to effectively dodge anything. And honestly, the first boss isn't too shabby. Good luck getting back onto the platform after you get knocked off. Add more hitpoints, and it'd be difficult enough. But yeah, the second boss is a complete pushover once you've gotten the Bikini and Magic Sword, which you can get as early as halfway through the second dungeon, if you're determined enough.
Killed the 3rd boss on my 3rd attempt, 1st boss on my 2nd so I'm not sure what you're talking about, the issue with the 2nd boss is that you can just out dps him if you get the armor OR the sword.
btw you're supposed to dodge the 3rd boss by dropping down not jumping over... n00b