The joke nobody else at the table got
Both are introverted intuitives, so they grasp each other’s abstract ideas quickly, and many such couples find they laugh at the same dark or absurd things. Conversation tends to be interesting, to the point and rarely dull. Each respects the other’s need for long stretches alone.
They also complement each other in a neat way. The INFP leads with introverted feeling (Fi), which is the INTJ’s third function: the private values INTJs hold but rarely show. The INTJ’s helper, extraverted thinking (Te), is the INFP’s least comfortable function. Each partner has, in full, what the other has only in part.
The chore chart incident
INTJs often dislike housework and would rather think about almost anything else, though they like the result to be orderly. INFPs can be fine with a bit of creative chaos. A familiar scene: the INTJ, tired of the mess, builds a shared chore spreadsheet with color codes and deadlines. The INFP feels managed, as if their home has turned into a workplace, and starts avoiding the kitchen. The INTJ concludes the INFP doesn’t care.
Decisions run the same way. The INTJ argues from outcomes (“this apartment is cheaper and closer to work”), the INFP from what feels right (“this one felt like us”). Each can hear the other’s reasons as beside the point. And INTJs often show love through planning and problem-solving rather than words, which can leave an INFP wondering whether they’re loved at all.
Giving the plan a reason and the feeling a voice
The INTJ can explain the value behind a plan, not just the plan: “I want the bills sorted because I don’t want us arguing about money.” That turns a system into a shared cause. The INFP can say plainly what matters most and let the INTJ handle the method. Both benefit from a small amount of chosen spontaneity, and from the INTJ saying out loud, now and then, the affection they assume is obvious.