Meet Hiroshi Jenkins, a rather reserved boy who lives with his mom and mostly just keeps to himself. Though he does have one secret, he has an imaginary friend, a yeti like being he calls Enigami that he talks and interacts with. However one day, he's beset by a boy who keeps pestering him to fight him and not in the traditional sense. See, he too has an imaginary friend and wants to prove he's the better fighter. And he isn't the only student at Hiroshi's school to have a imaginary friend as well. Hiroshi soon finds himself pulled into the battle between these beings, if only just to defend himself, though likewise finds himself making friends as well. But it soon turns out someone else in their area has taken an interest in these friends, and not just for fun and games.
- Abusive Parent: Charlotte's mom is more worried about her status and how her daughter's action will make her look in front of people. Apparently not caring that she's trying to help two boys (Hiroshi and Aran) to keep from from being implicated in a kidnapping case.
- Adult Fear:
- As the story opens, were shown some missing posters of a girl, one of the students that go to Hiroshi's school.
- Albert ends up attacked and goes missing with Hiroshi and Aren being suspected of being involved in his kidnapping.
- Connor ends up kidnapped right at the doorstep of his home while his mother is too busy looking at her phone.
- Crazy Jealous Guy: Conner turns out to be infatuated with Aran and gets jealous when Hiroshi and he start hanging out. Despite Hiroshi telling him he doesn't want to fight, Conner practically forces him into one and has to be calmed down by Aran to finally stop.
- Fun with Acronyms. The title, IF, stands for "Imaginary Friend".
- Imaginary Friend: The basis of the series, many of the kids have them (or as as Aran calls them, "Companions") and usually use them in battles that wouldn't be out of place in Pokémon.
- In the Hood: A mysterious figure that keeps attacking those with imaginary friends is cited to wear a yellow hoodie.
- Invisible to Normals: Normal people can't see the imaginary friends, only those that likewise have one of their own.
- Laser-Guided Amnesia: Whatever people are taking imaginary friend ends up inflicting this on their user once they're
- Let's You and Him Fight:
- Albert does this to Hiroshi, wanting to fight for no other reason than just to see who has the strongest Companion.
- Aran and Charlotte nearly comes to blows over a disagreement about a boy that attacked Charlotte but was being forced to do so. Hiroshi breaks them up before they get too far.
- The Mentor: Aran serves as a teacher to Hiroshi, training him how to properly fight with Enigami..
- Parental Neglect: Connor's mother is very inattentive of her son. Shown as early as the first strip where she's too busy looking at her phone than paying attention to what he's doing. This results in Conner getting kidnapped right at the doorstep of his home later as she doesn't bother to answer the door when some men come to do just that. When Connor is later found, she utterly blames herself for letting it happen.
- Stalker Without a Crush: Albert who, at the start of the series, constantly keeps pestering Hiroshi to fight him to his annoyance. Doing this even while Hiroshi is in his classes despite Hiroshi making it obvious he isn't interested. Ultimately Hiroshi is forced to fight him just to get him to back off.