I think bun combining is broken. It seems that no matter which two buns you choose, you always get Miss You Turbo.
First, this is going to be a wall of text, sorry, but it can't be helped due to the subject.
Sadly, the Bun Fusions are glitched, even in the original game (so it's not a problem caused by the translation). However, I was able to come up with a list of "good" fusions. I'll list it here, in case you want to try it:
Bun 1 + Bun 2= Result
Mandarin Bun +Training Bun=Fish
Mandarin Bun +Sexy Bun=Bun Stone (2X EXP/Gold when used in battle – Single use)
Mandarin Bun +Salvation Bun=Defense Seed
Mandarin Bun +Holmes Bun= Bun Armor (Armor for MC – Reflects enemy Psycho attacks)
Mandarin Bun +Gold Bun=Life Seed
Prayer Bun +Mandarin Bun=Psycho Def. Seed
Prayer Bun +Training Bun=Shellfish
Prayer Bun +Sexy Bun=Chinese Medicine
Prayer Bun +Salvation Bun=Bun Bracelet (Access. – All [Raises Parameters])
Prayer Bun +Holmes Bun=Bun Sword (Weapon for MC)
Prayer Bun +Gold Bun=Speed Seed
Training Bun +Sexy Bun=Bun Helmet (Helmet for MC – Blocks Status Effects)
Training Bun +Salvation Bun=Bun Shoes (Shoes for MC – Restore HP when walking)
Training Bun +Holmes Bun=Psycho Seed
Training Bun +Gold Bun=Bun Clothes (Armor for MC & Basil)
Sexy Bun +Salvation Bun=Spirit Seed
Sexy Bun +Holmes Bun=Bun Pajamas (Armor for Mina)
Sexy Bun +Gold Bun=Bun Necklace (Access. – All)
Salvation Bun +Holmes Bun=Bun Bullet (Item: Bomb)
Salvation Bun +Gold Bun=Strength Seed
Holmes Bun +Gold Bun=Bun Underwear (Helmet for Heath)
Now, before you head off to see the Bun King and start combining the different buns, I need to remind you that the bun combinations are glitched. What I saw (and this might be different for you, ymmv), is that the FIRST time you make a bun combination, it WILL work flawlessly. However, if you immediately go back to the Bun Combination screen and proceed to combine another pair, you WILL end up with a somewhat random (and totally wrong) item, usually a "Poison Ball".
What I did was this:
1) I made a Defense Seed, worked fine. I left the Bun King screen and went to replace the two buns I had just used up.
2) Once I had all buns again, I went back to the Bun Combination screen.
3) After a lot of trial and error, I realized that the NEXT time after the FIRST combination (in step 1), your combination will be an incorrect item. So...knowing this, I decided to make a "sacrificial" combination using the two quickest buns to obtain (that would be Mandarin Bun = Mama Island and Training Bun = Angkor Wat). You can replace these buns the quickest.
4) Enter the Bun Combination screen, make a Quick Save (just in case, that way you can reload if it doesn't work right), then combine the "sacrificial" Mandarin Bun and Training Bun, the result doesn't matter. Immediately, go back to the Bun Combination screen and combine the buns you really want (the result *should* be correct). Repeat from step 2 until you're done.
Some Buns are...more of a hassle to obtain than others (I'm looking at you, Gold Bun...having to walk to El Dorado). Nonetheless, you WILL have to return there to obtain the Gold Bun, sooner or later. This is where you'd think, "Ha! I'll just speak with that NPC, get another Gold Bun, then immediately jump into the Bun Combination screen, use my newly-acquired Gold Bun, then exit so I can get another Gold Bun by speaking (again) to the NPC right by me!" Good thinking, except that, in my experience, it ALWAYS resulted in a failed item. I actually had to LEAVE the village/island/NPC's location where I obtained a bun, THEN I'd jump into the Bun Combination screen (make a quick save), then try it again. More often than not, after one "sacrificial" combination, my next combination would produce the correct item. Sometimes, even the second combination would fail, in which case I'd reload my quick save, LEAVE the Bun Combination screen completely, then move somewhere else on the map (anywhere else, doesn't have to be far, just nowhere near NPC's).
After moving on the map, I'd try it again (making sure to use a new quick save), then tried the "sacrificial" combination followed by another (usually good) combination.
If all this sounds like it's a pain...yeah, it was. If you're at the Bun King, it's *probably* to make Seeds to increase your stats.
Life Seed = Can be bought at the Penguin Market
Strength Seed = Sand Whale has these, so don't waste your time trying to make this
Speed Seed = Can be bought at the Penguin Market
Defense Seed = Mandarin Bun + Salvation Bun
Spirit Seed = Sexy Bun + Salvation Bun
Psycho Seed = Can be bought at the Penguin Market
Psycho Def. Seed = Prayer Bun + Mandarin Bun
That's part of the reason why I kept (for nearly the entire game) both Power and Mind Chakras linked, so I could get the extra bonus every time I leveled up. After I hit level 99, most of the stats were already at max, 99, so I only had to get around 15 seeds total.
Also, if you do plan on spending time with the Bun Combinations, I can't emphasize strongly enough to make a quick save JUST BEFORE you make the combinations. If they fail, you can just reload, move somewhere else, then try it again (instead of, you know, having to fly all over the world again to track down the buns again).
Incidentally, I was only able to make TWO of the "Bun Bracelets" before it glitched out completely. Now, no matter how many "sacrificial" combinations I make, I always end up with "Bun Medicine" (everything else works fine, though, just this item did a "double glitch" on me).
Good luck, and hope this helps!