Hi, hello, wonderful person on the internet! Just wanna sneak this in here because being properly educated is very important :)
Incest is sexual activity or marriage between people who are closely related by blood, adoption, or marriage. It is not love; this is romanticizing a form of ABUSE.
I really, very much hope this helps! Have an amazing rest of your beautiful Day!! :DD

My view is: Incest is blood relationships rather than being raised in the same institution or sharing an adoptive, non-biological connection. Why: that's the legal definition, I just personally believe it's OK, it's not hurting anyone, and I think of the basic scientific reason - incest is illegal because inbreeding causes health defects.
Others view: Incest includes all situations where 2 people are raised together. That's fine, idc.
There's no wrong way to think, just a difference in views and moral/societal expectations.