4.306 out of 5 from 225 votes
If you liked the protagonist from Trinity Seven, you could try reading Tsuki Tsuki!. The male lead in Tsuki Tsuki! also has this laid back attidude and overall coolness (but not as much as the guy from Trinity Seven). This said Tsuki Tsuki! has a more harem feel to it and it also has some pointless ecchi.
Both Zero no Tsukaima and Trinity Seven feature your average Japanese boy being sucked in into a world of magic (though the guy in Trinity Seven doesn't travel through dimensions) and into a magic academy on top of that. Now in this new situation he finds out that he is actually extremely powerful. There is one major difference though, Saito from Zero no Tsukaima isn't cool outside of combat at all (with the few exceptions of showing his cunning side), on the other hand Arata from Trinity Seven can stay cool (almost) all the time. Even though both of them flirt with all the girls in their respective harems, somehow Arata doesn't give of that unpleasant "indecisive male lead" vibe like Saito does. If you want to read something like Zero no Tsukaima, but with cooler male lead, then Trinity Seven might be what you are looking for. Same with Trinity Seven, if you liked it, want to read something similar and don't mind an annoying male lead, then Zero no Tsukaima might just do the trick.