No, he is the snake that gave Eve the apple that got her and Adam kicked out of Heaven.

Except he quite clearly doesn't believe that. But given this is Sagara we're talking, he may have just been trying to get Mai to doubt Kouta's motivations- which he failed to do (just as planned...?).

Honestly it's impossible to make heads or tails of what the hell is going through Sagara's head. But right now I'm about 80% certain he has something to do with Grapenut going full raisin next episode.

I think he just toys around by saying that stuff.

I'm not. Ryoma makes the Yomotsu Heguri lockseed. He has scanned Kiwami and watched the power of the golden fruit. In the preview we see him with Mai (who contains the golden fruit) and Mitsuzane in his lab. He will use a fragment of the golden fruit to create the new lockseed, either by doing a complete new one or by altering the Budou lockseed.

I think that fits too good. Ryouma clearly built up his interest in Kiwami and the golden fruit, I think he will use Mitsuzane as a test subject. He will cut out a little part of the fruit and use it. That’s also an explanation on why the lockseed causes pain, its not properly created and unbalanced, unlike Kiwami.

Maybe Sagara pops in to help, but I doubt it.

I thought it was pretty much confirmed at this point that Sagara alone is the one who will give the Lockseed to Micchy...

Confirmed by whom? Is that some spoiler-stuff I'm not aware of? If yes just say it is, I don't want to know more about it. And don't take what I sayed about Ryoma creating it for granted, I'm just speculating.

I kinda second this. Ryoma creating/altering the Budou Lockseed would make so much sense, as he's shown to have given mods to his own Genesis Driver/Lemon Energy Lockseed.

Yeah. Spoilery episode descriptions that haven't ever been wrong before. I fully agree with your logic, but it doesn't look like that's what'll go down.

Well, episode 42 answered a question here.

He's Helheim itself.