I believe Angels had sexual relations with human woman on earth when they came down to earth and saw that the daughters of men where fair..
So you believe Angels cannot have corporial bodies?... Then who where the ones who visisted Abraham and his wife? who ate food that Abrahams wife prepared for them in Genisis 18??? read Genisis 18 and note when Abraham said ::::
Genesis 18:2 "And he lift up his eyes and looked, and, lo, three men stood by him: and when he saw them, he ran to meet them from the tent door, and bowed himself toward the ground, {3} And said, My Lord, if now I have found favour in thy sight, pass not away, I pray thee, from thy servant: {4} Let a little water, I pray you, be fetched, and wash your feet, and rest yourselves under the tree: {5} And I will fetch a morsel of bread, and comfort ye your hearts; after that ye shall pass on: for therefore are ye come to your servant. And they said, So do, as thou hast said.""""
Abraham offered to wash their physical feet and give them physical food to eat.. How can you physically wash the feet of Spirits or how can Spirits consume physical food.. Read all of chapter 18 and see how Two of the 3 went on to Sodom while the LORD stayed with Abraham to talk.. note how the last verse says..
Genesis 18:22 "And the men turned their faces from thence, and went toward Sodom: but Abraham stood yet before the
LORD."
Go on to read Genisis 19: the story of the destruction of Sodom The first part of the chapter makes it clear the two that went to Sodom where Angels:: We read::
Genisis 19: KJV 1 And there came
two angels to Sodom at even; and Lot sat in the gate of Sodom: and Lot seeing them rose up to meet them; and he bowed himself with his face toward the ground; 2 And he said, Behold now, my lords, turn in, I pray you, into your servant’s house, and tarry all night, and
wash your feet, and ye shall rise up early, and go on your ways. And they said, Nay; but we will abide in the street all night. 3 And he pressed upon them greatly; and
they turned in unto him, and entered into his house; and he made them a feast, and did bake unleavened bread, and they did eat.
So here we read of two Angels eating food prepared for them by Lot.... If angels can only be spirits then how can they eat food??? When you read on about the men of soddom who came to the house because they wanted to have sexual realtions with the angels. You read how the Angels physically pull lot by hand into the building and struck the men outside with blindness..
(Genesis 19:9-11) "And they said, Stand back. And they said again, This one fellow came in to sojourn, and he will needs be a judge: now will we deal worse with thee, than with them. And they pressed sore upon the man, even Lot, and came near to break the door. {10} But the men
put forth their hand, and pulled Lot into the house to them, and shut to the door. {11} And
they smote the men that were at the door of the house with blindness, both small and great: so that they wearied themselves to find the door."
There is no way that one can believe that Angels cannot come in corpral form.. Again in the New testament we read..
(Hebrews 13:1-2) "Let brotherly love continue. {2}
Be not forgetful to entertain strangers: for thereby some have entertained angels unawares."
How do we entertain strangers? We invite them into our homes and offer them drinks and food and put them up for the night. Entertaining strangers is showing hospitality to them.. One can only do that to Angels if the Angels come in physical bodies.. 
