The main character is introduced as a powerful knight holding back the enemy as his princess escapes at the end of a power struggle in which his faction loses. He takes pride in his honorable sacrifice for his princess to have a chance of survival but is confused when in his dying moment his princess returns to him to instead die with him instead of living without him. The MC then wakes up as his younger self on the day of his graduation from the knight academy. In the ceremony the MC manages to impress the three princesses attending (including his 'future' princess) with his outstanding skill and they each offer to take him on as their knight and offer him various perks but plot twist the MC refuses all of them to instead take up post as a capital defense knight which is a glorified police officer. Now I quite like this action since the MC is not only a fresh graduate from knight school but is also a commoner so it makes sense for him to not immediately join a princess faction and face political backlash but instead take a modest position and gain achievement and I thought the author made a good story choice but no, his real intention in joining the cdk was to instead have a cozy and relaxing life this time around. This is the first immersion break for me as a supposedly loyal and honorable knight who gains a second chance at life wants to instead just relax and let the story play itself out without him. This is a major fumble but I thought the author had a chance to salvage it as the princesses were really into him for rejecting them and so they had a chance to rope him in later on in the story so I kept reading.

The second fumble occurred when the MC finds one of the princesses (in disguise) being scammed by a powerful merchant. The merchant was getting aggressive when the MC stepped in to resolve the dispute. Instead of going full on oblivion guard mode "stop right there criminal scum" and do some political maneuvering for political favors or anything, the MC instead performs an impromptu on-site investigation, into an on-site trial, into an on-site punishment for violating the law. Like author please, you described the cdk as a glorified police but here they look like an unstoppable judge/jury/executioner force ala robocop style. At this point the author has not described the role of the cdk, other than a patrol around the capital, nor the command structure, other than two seniors who came to haze him on his first day, and now shows the cdk as the highest authority in the capital which is, in my opinion, bad writing.

The third fumble occurred when the MC and his senior in the cdk were invited to the birthday party of one of the princesses. During the party the head knights of two princesses were to duel for entertainment. The duel escalates until they start using their magic aura and placing the (high-ranking) guests around in danger. The MC starts worrying that if nobody stops them then the blame for this disaster would be placed on his senior sitting beside him. The MC seriously thought that the blame for two head knights going overboard would be placed not on the knights themselves, not on their respective princesses, not even on the active duty guards that are watching this unfold, but on the off duty guest capital defense knight senior who btw is just one year his senior. Uhm.. Ok? But why? The author doesn't explain. And the way the MC chose to stop the dueling knights was dumb too. See, the MC wants to hide his power so he decides to somehow create a smokescreen on the stage, have a dramatic entrance to exchange dialogue with the knights and ask them to surrender, and when they inevitably refuse he defeats one knight with ease and then the next one with a bit more difficulty but then uses the second knight's spear to collapse the whole stage and in the confusion he places the two knights and their weapons so it looks like they defeated each other. Masterful plan. Absolutely brilliant. /Sarcasm

After that immersion break I was done with this story.

MC accept the whole regression too easily and doesn't seem to mind much of her princess even though he seem to serve her in his past

1st princess is obsessed with his talent, 2nd princess seems to remember something from the past or is genuinely interest in MC and 3rd princess deemed him fun and interesting but as the plot goes the last route is predictable