It happened on Westpark Drive near Vineyard around 9 p.m. Tuesday.
Whoa! Look at the damage to that house
Deputies said the 20-year-old driver was speeding while going westbound on Westpark Drive when he crashed through a fence and hit the house.
The driver suffered minor injuries, but the girlfriend's father told ABC13 that his daughter's chest was deeply scraped by the pieces of wood from the fence debris. He said her chest injuries are severe and that he could see her heart.
The father said the boyfriend worked to keep the 20-year-old alive.
Three people inside the house were not injured.
Witnesses say a second vehicle was seen speeding alongside the wrecked car before the accident.
The driver says he was hit by that other car, but investigators are trying to see if something else was happening prior to the crash.
"Trying to see if this was indeed a racing incident or if he just lost control and went off the roadway," Harris County Sheriff's Office Deputy Dashana Cheek-McNeal said.
Follow Jeff Ehling on Facebook and Twitter.