Really, it's just an expression div (Alice in Wonderland subsection**)

Ya gotta wonder when the young don't know the difference between the real meaning of a word and the slang definition, eh ??
blow ¹  (bl)

v. blew (bl), blown (bln), blow·ing, blows

v.intr.

1. To be in a state of motion. Used of the air or of wind.

2. To move along or be carried by or as if by the wind: Her hat blew away.

3. To expel a current of air, as from the mouth or from a bellows.

4. To produce a sound by expelling a current of air, as in sounding a wind instrument or a whistle.

5. To breathe hard; pant.

6. To storm: It blew all night.

7. To release air or gas suddenly; burst or explode: The tire blew.

8.

a. To fail or break down, as from being operated under extreme or improper conditions: The furnace blew during the cold snap.

b. To melt or otherwise become disabled. Used of a fuse.

9. To spout moist air from the blowhole. Used of a whale.

10. Informal To boast.

11. Slang To go away; depart.

v.tr.

1. To cause to move by means of a current of air.

2. To expel (air) from the mouth.

3. To cause air or gas to be expelled suddenly from: blew a tire.

4. To drive a current of air on, in, or through: blew my hair dry after I shampooed it.

5. To clear out or make free of obstruction by forcing air through: constantly blowing his nose in allergy season.

6. To shape or form (glass, for example) by forcing air or gas through at the end of a pipe.

7. Music

a. To cause (a wind instrument) to sound.

b. To sound: a bugle blowing taps.

8.

a. To cause to be out of breath.

b. To allow (a winded horse) to regain its breath.

9. To demolish by the force of an explosion: An artillery shell blew our headquarters apart.

10. To lay or deposit eggs in. Used of certain insects.

11.

a. To cause to fail or break down, as by operating at extreme or improper conditions: blew the engine on the last lap.

b. To cause (a fuse) to melt or become disabled.

12. Slang

a. To spend (money) freely and rashly. See Synonyms at waste.

b. To spend money freely on; treat: blew me to a sumptuous dinner.

>>>>   13. Vulgar Slang To perform fellatio on.(if you don't know what this is, look it up for yourself !)

                                                          (thefreedictionary.com)

Really folks, it's just an expression. Be Careful.

** 'When I use a word,' Humpty Dumpty said, in rather a scornful tone, 'it means just what I choose it to mean — neither more nor less.' Lewis Carroll - "Through the Looking Glass