jonas was a product of the guardians that raised him - the duke only saw him as a byproduct that he needed to keep in order to marry the duchess, who adored what was left of her princess. but being spoiled and lavished by the duchess made him like many of the rich noble characters we see, and he only serves his own selfish desires because that was enabled in him all his life. if people cared more about him as a person and less as an accessory who knows what kind of person he would have been - a bit more like the ml perhaps if he was taught more on the honor and duty he should have...