Oh man, the parallels in these endcards.
So on the top left we have Kagami and Kuroko supporting the same basketball, they are looking soulfully into each other’s eyes. Down in the corner, one bag is supporting the other and stopping it from falling down.
On the top right we have Teikou Aomine and Kuroko. The ball lies abandoned in the corner. Aomine is looking down painfully at Kuroko, and has covered Kuroko’s eyes so he cannot see. Kuroko is not resisting him, but one hand is raised slightly as if he is not completely okay with it. Aomine’s bag is resting beside him up on the invisible bench, while Kuroko’s lies fallen on the ground unsupported.
On the bottom left, they both have their own basketballs that they are carrying now, and Kagami is the one lying down this time. But all of Kagami’s attention is on his ring, while Kuroko is ostensibly facing forward but looking at Kagami out of the corner of his eyes unhappily. The bags are still together though, with the first bag now supporting the second bag from falling.
On the bottom right, Kagami is lying down with one hand supporting his basketball like before, but the other is fisted around Himuro’s ring - forcing Himuro to look at him - while his own is back around his neck. Himuro’s ball is also abandoned in the corner, though from its position it is possible that it had rolled down due to Kagami grabbing at Himuro. We can see that Kagami is staring up at Himuro determinedly, but due to his fringe we cannot see Himuro’s eyes nor tell what expression he is making. Kagami’s bag stands upright in the corner, but Himuro’s bag lies fallen on the ground. It is the only bag that is unzipped. Something is falling out, though the towel draped over it hides most of it from sight.
In conclusion, SYMBOLISM (there is so much symbolism in the endcards, someone must be having a lot of fun).