In Mahou Sensei Negima!, Les Yay pretty much defines Setsuna and Konoka's relationship. Setsuna harbours a Bodyguard Crush so enormous it can be seen from outside the galaxy (which isn't much of an exaggeration considering literally Everyone Can See It, including Negi), while Konoka is very much The Tease towards "Set-chan". For a long time it was uncertain what their relationship would be, Setsuna convinced she is not worthy to be so close to Konoka and Konoka herself remaining guarded about the extent of her feelings, but on an almost constant basis Akamatsu would tease people with hints from both sides, comedic and serious, detailed in specifics in the series' extensive Ship Tease entry.
Probably the most blatant early example is a small arc where Setsuna defends Konoka in battle dressed as a male samurai and Konoka done up as her princess in distress against anenemy who is practically dripping with Foe Yay. This is so obvious the other girls all assume the whole thing is an actual date and commence squeeing their support for Konoka's and Setsuna's love. Also after they're separated at the start of the Magical World Arc, the chapter they're reunited in is called We meet again, My Beloved.
Chapter 252 beats the above in blatantness and may have just moved this relationship from sub-text to text-text. Good grief, Konoka. Pactios don't need to take that much time. Nor do they require that much tongue. In fact, they don't require tongue at all. Not that there is anything wrong with that.
Negi and Fate. Holy crap. With each of their encounters it became more and more obvious that if Fate weren't the poster-child for The Stoic he would be all over Negi like Tsukuyomi on Setsuna, with a particular emphasis on In Love with Your Carnage. By the time Tsukuyomi eventually confirmed it such a thing had become highly redundant.
Chapter 336 Lampshades it: after Fate says "He already belongs to me," the last page reads "The strongest love(?) rival appears!!"
There's also how Fate tends to act like a Tsundere for Negi.
Shiori has the power to "become" another person, copying their appearance, memories, and powers... by kissing them. Not like a peck on the cheek, either; she makes out with her target until they pass out due to lack of oxygen. So far, she has used this power once... on Asuna.
The Chichigami. She only appears briefly, but seems to exist for the sole purpose of Skinship Grope-ing literally every girl she can get her hands on.
Chapter 341 features Konoka glomping Asuna by way of a greeting, Setsuna wanting to wash Asuna's back, and Setsuna stating she lives to protect Konoka and carrying her in a Bridal Carry. Also Setsuna has a fantasy of a perfect future with Konoka.
Chapters 343 and 344 features a bit of Setsuna/Asuna.