BUAHAHAHAHA - Age gap this, age gap this. This is not an adult mag. Good thing you didn't read that one story where the guy was 500 years older than his bride (well, he didn't know there was an age gap till later, because she lied and said she was 500 too - when she was 5 years old)! You surely would have been hating on that too. To me, this story is about her magic, not about her marriage. And I will enjoy it to the fullest.
I mean, she was 18 when she died and now she's 15, meaning she's more like 32 in her mind. What bothers me a little more than the age gap is how this will be his 3rd marriage, while it's her first. Holy crap, even when he never loved his previous wives, but that actually makes it worse. I thought she'd be marrying the guy who saved her or the current young king, but oh well.
I was going to start a topic about story inconsistency but after reading a few comments, I feel no one would care about parents taking their child to a magician town to find a healer for their daughter, when it's know healers are from the church and don't get along with magicians . . . . because everyone is too busy drooling over the MC, those comments are hilarious