[ ANSWERS ] All flower meanings were primarily taken from this page.
[ DAY ONE ] violet honesty
I'd chosen violets as the first flower since it's the English name of the module / outfit KAITO was sporting while hosting the hanamogera game. I'd initially considered drawing him in such here too, but felt that, since he was already wearing it, it wouldn't provide enough a hint towards his clothing choice possibly meaning something as well. That's why he is mostly naked, or bare -- an adjective generally associated with honesty. The reason he's still in half a shirt, though, is because his sleeve is upon his heart ... instead of his heart upon his sleeve. OTL ; SAME THING, THOUGH? ...
[ DAY TWO ] red spider lily abandonment lost memory never to meet again
I can recommend Higanbana no Saku Yoru ni, to be honest. Nice VN. manga's a little less so. MORE ON TOPIC -- This was a hard one, I'll admit, but I figured I'd crank up the level after the somewhat easier starter. I tried putting him in a generally desperate / desolate pose, to go with the various meanings of this flower. The reaching gesture was supposed to look somewhat in vain, because of the abandonment / inability to meet the other again. The lost memory I tried to depict through him touching his face / forehead, as if he was having a heavy headache or some sort of amnesia through which he could not remember. Finally, he's wearing ( most of ) his V1 clothes ( though stripped of his trademark coat ) for a reason here -- all the flower meanings mentioned above.
[ DAY THREE ] pink rose confidence happiness trust
We firstly have the fistpump here ( or something that is supposed to look like it ), which is generally the mark of an achievement, achievements making you both confident and happy. The wink ( with animu sparkles for generic indication of glee / overconfidence ) are supposed to further contribute to this feeling. Originally, he was reaching, which is still somewhat visible in the pose, an openly offered hand generally being a symbol of trust. I swapped this idea for him offering the letter, however, for multiple reasons. The first is that the rose just so happens to be the flower of love, with pink roses ( in western flower languages ) conveying adoration or romantic interest, so this could very well be a love letter. It is, however ( reason 2 ), not that: he's winking at you so very cheekily because someone asked if he liked roses, so he here asked you to find him some in reference to that message.
[ DAY FOUR ] dandelion respect
A bow is not only one of the most respectful gestures out there, he's also trying to use it to emulate the posture of the dandelion here as they tend to sag forwards a little under the weight of their heads. His clothes are supposed to be of the proper and respectable kind, but the main reason he's wearing them is because they go with the glasses. The glasses are important. The spectacles. Spectare. Respectare? No? OTL
[ DAY FIVE ] forget - me - not true love
To convey the Japanese meaning of this flower, he's touching his heart. To convey the western meaning, he's touching his forehead. The shape of his scarf is also supposed to, slightly abstractly, be one of a heart .. but, I'll admit, I was mostly aiming for the literal meaning in the flower name here, through combining the flower's colors with his V1 outfit. Please do not forget me.