By Ken Akamatsu. Released in Japan as "Mahou Sensei Negima!" by Kodansha, serialization ongoing in the magazine Weekly Shonen Magazine. Released in North America by Del Rey.
Well, in case you felt that the Tournament arc back at Mahora wasn't enough, we now get the climax to another tournament arc, as Negi and Kotaro are fighting Jack Rakan and Kagetaro. The prize? One million drachmas, which Negi wants to use to free Ako, Natsumi and Akira from slavery. Jack, however, says in order to get that he'll need to beat him. Which is kind of impossible, as Jack is a 'broken cheat' character who is mind-numbingly touch and strong.
The battle itself is interspersed with flashbacks to two days before it, where we see Negi researching Jack and finding out no, he really is as hard to defeat as everyone says. In case it wasn't obvious, Negi notes that much of Jack's 'dumb jock' persona is just a persona, and that he got where he is by training to get better every day of his life. Negi being the current #2 in Negima's angst meter (Setsuna is still tops), and is doing all this research convinced he's going to lose in two seconds.
This leads to a confrontation with Tosaka, who earlier discovered Negi running around as a ten-year-old. Tosaka's motivations are handled very well here - Akamatsu doesn't like to do straight out jerk characters, so we see why his backstory makes him really pissed off at what Negi's doing - as well as monstrously angry when Ako tries to solve the blackmail dilemma by offering herself to Tosaka. Another grumpy jerk who's secretly a softie at heart.
My favorite part of the volume is the saddest scene, though. We all knew it had to come sooner or later, and many volumes have been dedicated to her not catching on. However, Ako's discovery of Negi's secret, and subsequent reaction, are absolutely heartbreaking. It's telling that he draws this with Ako naked in the hot springs, and yet there's not even a hint it's for fanservice. This is pure cleansing of the soul. And it makes Ako's support of him later on all the more heartwarming.
As for the fight itself, it's pretty awesome, as shonen fights go. Everyone gets to show off their skills. We get to see the girls reacting the way we would if we were there. And Negi is really amazingly clever in this, showing, as noted by Rakan and the 'fake' Evangeline, that his true strength is his inventiveness. And, the outcome aside, the objective is achieved: the girls are freed. (I note the scene where the girls have their collars unlocked by Negi and Kotaro is drawn in a very... suggestive way. Akamatsu may be doing shonen fight manga, but it's not just his editors who want that fanservice. The whole scene is reminiscent of 'deflowering'... while still being perfectly innocent, of course.)
And so the tournament is finished, as has Negi's training with Rakan. Which means we no doubt will get new plot points in Volume 28. Along with, if I recall, a big, big chapter for anyone who likes their KonoSetsu pairing. :)